Institute of Nuclear Physics and Engineering

Official website: inphe.mephi.ru

N.Barbashina

 

Natalia S. Barbashina
Executive Director

A.Vasiliev

 

Alexander Vasiliev
Scientific Supervisor

Strategic aim of the INPhE

The strategic aim is the creation and development of the world level scientific and educational center in the field of nuclear physics and technology, radiation materials science, elementary particle physics, astrophysics and cosmophysics.

The strategy of the INPhE development is aimed to taking leading positions in the following areas:

● nuclear energy of the XXI century (multicomponent nuclear energy, closed fuel cycle, nuclear waste disposal, NPP safety);
● radiation and beam technologies (materials science, radiation physics, electronics, etc);
● high-energy physics and elementary particle physics, astrophysics and cosmophysics (new states of matter, ultrahigh-energy particles, spin and polarization effects, properties of neutrino, and gamma-ray astronomy);
● applied aspects of the solar-terrestrial physics, improving of methods for monitoring of potentially hazardous processes in the Earth's atmosphere and near-Earth space;
● new system of training of personnel for the science-intensive sectors of the economy.

 

Education:

  • Automation and Electronics
  • Radiation Safety
  • Nuclear Physics and cosmophysics
  • Experimental methods of nuclear physics
  • Elementary particle physics
  • Physics of extreme states of matter
  • Physics of nuclear reactor
  • Materials science
  • Thermophysics
  • Technologies of closed nuclear fuel cycle
  • Engineering computer simulation
+

Research:

  • Fundamental Research and Particle Physics
  • Atomic Power Industry
  • Nuclear Systems and Materials
  • Scientific and educational center NEVOD
Faculty: 354
Engineering
staff:
 412
Students: 2692

Structure:

  • Department of Radiation Physics and Safety of Nuclear Technologies (#1)
  • Department of Automatics (#2)
  • Department of Theoretical and Experimental Physics of Nuclear Reactors (#5)
  • Department of Experimental Nuclear Physics and Cosmophysics (#7)
  • Department of Materials Science (#9)
  • Department of Experimental Methods of Nuclear Physics (#11)
  • Department of Thermal Physics (#13)
  • Department of Elementary Particle Physics (#40)
  • Department of Physics of Extreme States of Matter (#60)
  • Department of Closed Nuclear Fuel Cycle Technology (#89)
  • Department of Computer Engineering Simulation (#91)
  • Scientific & Educational Centre NEVOD
  • Astrophysics Institute
  • Interdepartmental Laboratory of Experimental Nuclear Physics
  • Interdepartmental Laboratory of Silicon Photomultipliers
  • Interdepartmental Laboratory of Perspective Technologies of New Material Creation
  • Department of Automation, Control and Diagnostics (IATE MEPHI)
  • Department of Mechanics and Strength of Nuclear Power Plant Construction (IATE MEPHI)
  • Department of Equipment and Operation of Nuclear Power Plants (IATE MEPHI)
  • Department of Design and Engineering of Nuclear Power Plant Reactors (IATE MEPHI)
  • Department of Thermal Physics (IATE MEPHI)
  • Department of Ecology (IATE MEPHI)
  • Research
  • Education
  • Faculty
  • Collaboration
  • Publications

Ecology:

Development of technologies for decommissioning of nuclear power facilities (Green Field)

  • Computational and experimental rationale and synthesis of perovskite compounds
  • Techniques of estimation of contamination of NPP materials

Innovations

  • Technologies of radioactive waste consolidation
  • New nuclear power technologies

Partners

IAEA, SC Rosatom, ENEN, SC Roscosmos, NRC "Kurchatov Institute"

New forms of energy and subnuclear technologies:

Development of techniques for the detection of quark-gluon matter, dark matter particles and neutrinos

  • Physics of heavy ions and quark-gluon matter
  • Searching for new states of nuclear matter and applied research at the setups
  • Astrophysical experiments and cosmology
  • Search for new physics at colliders

Innovations

  • New technologies of nuclear radiation registration
  • NPP neutrino monitoring
  • Nuclear medicine

Partners

NRC "Kurchatov Institute", CERN , JINR, INFN, BNL, ORNL

Safe nuclear energy:

Tolerant nuclear fuel, non-proliferation and guarantees, new principles of the nuclear power plant control

  • New principles of detection of the nuclear reactor parameters
  • New technologies of nuclear fuel consolidation

Innovations

  • New materials
  • New reactors:BN-1200 and VVER-SKD
  • New technologies of accounting, control and physical protection of nuclear materials

Partners

IAEA, NEA/OECD, SC Rosatom, IMET RAS, ENEN

Power supply:

Two component nuclear power with a closed nuclear fuel cycle

  • Development of systems based on electro-nuclear technologies (ADS)
  • Innovative sources of neutrons
  • New heat carriers

Innovations

  • Multipurpose nuclear reactors
  • New nuclear power technologies
  • Materials for renewable power industry

Partners

IAEA (G-IV, INPRO), SC Rosatom, NRC "Kurchatov Institute", ENEN, ORNL

Ecology:

Development of technologies for decommissioning of nuclear power facilities (Green Field)

  • Technology of the NPP decommissioning
  • Materials for the renewable power generation

New forms of energy and subnuclear technologies:

Development of techniques for the detection of quark-gluon matter, dark matter particles and neutrinos

  • Properties of quark-gluon plasma
  • Basics of dark matter particle and neutrino detection
  • Processes in the early Universe as the basis of the observed forms of energy

Safe nuclear energy:

tolerant nuclear fuel, non-proliferation and guarantees, new principles of the nuclear power plant control

  • Control and safe operation of SCWR
  • Tolerant nuclear fuel
  • Innovative construction materials
  • Technologies of protection against the nuclear material proliferation

Power supply:

two component nuclear power with a closed nuclear fuel cycle

  • Innovative Nuclear Reactors
  • Technologies of closed fuel cycle


Training Directions

Degree

Bachelor's degree programs

14.03.02 – Nuclear Physics and Technology

22.03.01 – Materials science and technologies of materials


Specialist's degree programs

14.05.01 – Nuclear reactors and materials

14.05.02 - Nuclear power plants:design,maintenance and engineering

14.05.03 - Technologies of isotope separation and nuclear fuel

14.05.04 - Electronics and Automation of Physical Installations

Bachelor's Degree/Specialist's Degree

Master's degree programs

14.04.02 – Nuclear Physics and Technology

22.04.01 - Materials science and technologies of materials

03.04.02 – Physics

14.04.01 - Nuclear energy and thermal physics


Postgraduate training program

03.06.01 - Physics and astronomy

14.06.01 - Nuclear, thermal and renewable energy and related technologies

27.06.01 - Control in technical systems

09.06.01 - Computer science and engineering

13.06.01 - Electric - and heat power

18.06.01 - Chemical technology

22.06.01 - Materials technology

Master's Degree/Postgraduate Training program

Foreign scientists - Co-leaders of the MEPhI Labs


Piero Spillantini (Italy) - PhD, prof., member of PAMELA and GAMMA-400 space experiments, H-index=48

e-mail:  spillantini@fi.infn.it

David Besson (USA) - PhD, prof. of University of Kansas, Chair of SiPM Laboratory, H-index=71

e-mail: zedlam@ku.edu

Alexander Bolozdynya - Dr of Science, prof., Deputy Head of Laboratory for Experimental Nuclear Physics of MEPhI, H-index=19

e-mail:  AIBolozdynya@mephi.ru

Alexander Vasiliev - Dr. of Science, prof., Scientific Supervisor, Russian chair of PANDA experiment, chair of the joint IHEP-MEPhI project SPASCHARM on spin study of strong interactions in Protvino, H-index=77

e-mail: Alexander.Vasiliev@ihep.ru

Andrea Chiavassa, PhD. - University of Turin and Istituto Nazionale di Fisica Nucleare, Italy. Professor of the Scientific & Educational Centre NEVOD, Co-director of the International Laboratory NEVOD-EAS, H-index=37

e-mail: andrea.chiavassa@to.infn.it

Michael Danilov - Dr. of Science, prof., Corresponding member of Russian Academy of Science, team leader of CMS MEPhI group, H-index=69

e-mail: danilov@lebedev.ru

Anatoli Romaniouk - PhD, prof., TRT project leader in the ATLAS experiment at LHC, H-index=45

e-mail: Anatoli.Romaniouk@cern.ch

Mikhail Skorokhvatov - Dr. of Science, prof., Russian group leader in the BOREXINO and DarkSide experiments, H-index=25

e-mail:Skorokhvatov_MD@nrcki.ru

Arkadiy Taranenko - PhD, associated prof., MEPhI group leader in international experiments HADES (GSI), NA61/SHINE (CERN) and PHENIX (BNL), H-index=44

e-mail:  arkadij71@gmail.com

Anatoly Petrukhin – Dr. of Science, prof., Scientific Director of Experimental complex NEVOD, Chief Researcher, Head of the Leading Scientific Schools "Physics of cosmic-ray muons", H-index=12

e-mail: AAPetrukhin@mephi.ru

Christian Spiering, PhD. - DESY-Zeuthen & IceCube 
Professor of the Scientific & Educational Centre NEVOD, H-index=53

e-mail: Christian.Spiering@desy.de

Ashot Chilingarian, PhD. - Director of the Alikhanyan National Laboratory, Armenia Professor of the Scientific & Educational Centre NEVOD, co-director of the International Laborator «Physics of Atmospheric Processes», H-index=43

e-mail: chili987@gmail.com

Dieter H.H. Hoffmann, Prof. Dr.Sc. Professor of the Technische Universität Darmstadt, Germany. Professor of the Department of Physics of Extreme States of Matter (dept. 60), H-index=46

e-mail: hoffmann@physik.tu-darmstadt.de

Hasebe Nobuyuki, Prof. Dr.Sc. Professor of the Waseda University, Tokyo, Japan. Professor of the Department of Experimental Nuclear Physics and Cosmophysics (dept. 7), H-index=18

e-mail: nhasebe@waseda.jp

Sparvoli Roberta, PhD. Associate Professor of the University of Rome Tor Vergata, Italy. Professor of the Department of Experimental Nuclear Physics and Cosmophysics (dept. 7), H-index=18

e-mail:  Roberta.sparvoli@roma2.infn.it

Maximilian Wolff, PhD. Associate Professor of the Uppsala University, Sweden. Associate Professor of the Department of Materials Science (dept. 9), H-index=13

e-mail:  max.wolff@physics.uu.se

Short Michael Philip, PhD. Associate Professor of the Massachusetts Institute of Technology, USA Associate Professor of the Department of Materials Science (dept. 9), H-index=8

e-mail:  hereiam@mit.edu

Alex Umantsev, PhD. Professor of the Fayetteville State University, USA Associate Professor of the Department of Materials Science (dept. 9), H-index=11

e-mail:  aumantsev@uncfsu.edu

Svetlana Kushpil, PhD. Researcher Nuclear Physics Institute of the CAS, Prague, Czech Republic Professor of the Department of Experimental Methods of Nuclear Physics (dept. 11), H-index=47

e-mail: skushpil@ujf.cas.cz

Vasily Kushpil, PhD. Researcher Nuclear Physics Institute of the CAS, Prague, Czech Republic Professor of the Department of Experimental Methods of Nuclear Physics (dept. 11), H-index=48

e-mail: kushpil@ujf.cas.cz

Borissov Alexander, PhD. Leading Researcher at the University of Heidelberg, Germany, Professor of the Department of Elementary Particle Physics (dept. 40), H-index=59

e-mail: aborisso@mail.cern.ch

Hasebe Nobuyuki, Prof. Dr.Sc. Professor of the Waseda University, Tokyo, Japan. Professor of the Department of Experimental Nuclear Physics and Cosmophysics (dept. 7).

e-mail: nhasebe@waseda.jp

Global Nuclear
Centers
CERN, JINR (NICA), National Laboratories of the USA (BNL, LANL, ANL), ITER, DESY, FAIR
Leading World
Nuclear Universities
Massachussetts Institute of Technology, USA; Texas A&M University, USA; Tokyo Institute of Technology, Japan; University of Manchester, UK; Karlsruhe Institute of Technology, Germany

Partner Countries of the State
Corporation "Rosatom"

NPP built by Russian projects (Czech Republic, Slovakia, Finland, Bulgatia, China, Republic of Belarus, Turkey, Vietnam, Bangladesh), Companies of NFC (Kazakhstan, Canada)
 
Interantional Organisations
IAEA, NEA/OECD, World Nuclear University, ENEN
 
2017
Inclusive search for supersymmetry using razor variables in pp collisions at root s=13 TeV / Aleksandrov,A; Matveev,V.; Bylinkin,A; Chistov,R.; Danilov,M.; Rusinov,V.; Azarkin,M; Dremin,I.; Leonidov,A.; // PHYSICAL REVIEW D. - 2017. - 95. - с.

Annotation:

An inclusive search for supersymmetry using razor variables is performed in events with four or more jets and no more than one lepton. The results are based on a sample of proton-proton collisions corresponding to an integrated luminosity of 2.3 fb(-1) collected with the CMS experiment at a center-ofmass energy of s root s = 13 TeV. No significant excess over the background prediction is observed in data, and 95% confidence level exclusion limits are placed on the masses of new heavy particles in a variety of simplified models. Assuming that pair-produced gluinos decay only via three-body processes involving third-generation quarks plus a neutralino, and that the neutralino is the lightest supersymmetric particle with a mass of 200 GeV, gluino masses below 1.6 TeV are excluded for any branching fractions for the individual gluino decay modes. For some specific decay mode scenarios, gluino masses up to 1.65 TeVare excluded. For decays to first-and second-generation quarks and a neutralino with a mass of 200 GeV, gluinos with masses up to 1.4 TeVare excluded. Pair production of top squarks decaying to a top quark and a neutralino with a mass of 100 GeV is excluded for top squark masses up to 750 GeV.

Charge-Dependent Directed Flow in Cu+Au Collisions at sNN =200 GeV / Alekseev,I.; Brandin,A.V.; Kochenda,L.; Kravtsov,P.; Nigmatkulov,G.; Okorokov,V.A.; Strikhanov,M.; // Physical Review Letters. - 2017. - 118. - с.

Annotation:

We present the first measurement of charge-dependent directed flow in Cu+Au collisions at sNN=200 GeV. The results are presented as a function of the particle transverse momentum and pseudorapidity for different centralities. A finite difference between the directed flow of positive and negative charged particles is observed that qualitatively agrees with the expectations from the effects of the initial strong electric field between two colliding ions with different nuclear charges. The measured difference in directed flow is much smaller than that obtained from the parton-hadron-string-dynamics model, which suggests that most of the electric charges, i.e., quarks and antiquarks, have not yet been created during the lifetime of the strong electric field, which is of the order of, or less than, 1 fm/c. © 2017 American Physical Society. / Alekseev,I.; Brandin,A.V.; Kochenda,L.; Kravtsov,P.; Nigmatkulov,G.; Okorokov,V.A.; Strikhanov,M.; // Physical Review Letters. - 2017. - 118. - с.

A measurement of the calorimeter response to single hadrons and determination of the jet energy scale uncertainty using LHC Run-1 pp-collision data with the ATLAS detector / Antonov,A.; Belotskiy,K.; Belyaev,N.L.; Bulekov,O.; Dolgoshein,B.A.; Kantserov,V.A.; Krasnopevtsev,D.; Romaniouk,A.; Shulga,E; Smirnov,S.Y.; Smirnov,Y.; Soldatov,E.Y.; Tikhomirov,V.O; Timoshenko,S.; Vorobev,K; // European Physical Journal C. - 2017. - 77. - с. / Antonov,A.; Belotskiy,K.; Belyaev,N.L.; Bulekov,O.; Dolgoshein,B.A.; Kantserov,V.A.; Krasnopevtsev,D.; Romaniouk,A.; Shulga,E; Smirnov,S.Y.; Smirnov,Y.; Soldatov,E.Y.; Tikhomirov,V.O; Timoshenko,S.; Vorobev,K; // European Physical Journal C. - 2017. - 77. - с.

Annotation:

A measurement of the calorimeter response to isolated charged hadrons in the ATLAS detector at the LHC is presented. This measurement is performed with 3.2 nb- 1 of proton–proton collision data at s=7 TeV from 2010 and 0.1 nb- 1 of data at s=8 TeV from 2012. A number of aspects of the calorimeter response to isolated hadrons are explored. After accounting for energy deposited by neutral particles, there is a 5% discrepancy in the modelling, using various sets of Geant4 hadronic physics models, of the calorimeter response to isolated charged hadrons in the central calorimeter region. The description of the response to anti-protons at low momenta is found to be improved with respect to previous analyses. The electromagnetic and hadronic calorimeters are also examined separately, and the detector simulation is found to describe the response in the hadronic calorimeter well. The jet energy scale uncertainty and correlations in scale between jets of different momenta and pseudorapidity are derived based on these studies. The uncertainty is 2–5% for jets with transverse momenta above 2 TeV, where this method provides the jet energy scale uncertainty for ATLAS. © 2017, CERN for the benefit of the ATLAS collaboration.

Measurement of the tt¯Z and tt¯W production cross sections in multilepton final states using 3.2 fb -1 of pp collisions at √s = 13 TeV with the ATLAS detector / Antonov,A.; Belotskiy,K.; Belyaev,N.L.; Bulekov,O.; Dolgoshein,B.A.; Kantserov,V.A.; Krasnopevtsev,D.; Romaniouk,A.; Shulga,E; Smirnov,S.Y.; Smirnov,Y.; Soldatov,E.Y.; Tikhomirov,V.O; Timoshenko,S.; Vorobev,K; // European Physical Journal C. - 2017. - 77. - с. / // European Physical Journal C. - 2017. - 77. - с.

Annotation:

A measurement of the tt¯ Z and tt¯ W production cross sections in final states with either two same-charge muons, or three or four leptons (electrons or muons) is presented. The analysis uses a data sample of proton–proton collisions at s=13 TeV recorded with the ATLAS detector at the Large Hadron Collider in 2015, corresponding to a total integrated luminosity of 3.2 fb- 1. The inclusive cross sections are extracted using likelihood fits to signal and control regions, resulting in σt t¯ Z= 0.9 ± 0.3 pb and σt t¯ W= 1.5 ± 0.8 pb, in agreement with the Standard Model predictions. © 2017, CERN for the benefit of the ATLAS collaboration.

Search for new resonances decaying to a W or Z boson and a Higgs boson in the ℓ+ℓ−bb¯, ℓνbb¯, and νν¯bb¯ channels with pp collisions at s=13 TeV with the ATLAS detector / Antonov,A.; Belotskiy,K.; Belyaev,N.L.; Bulekov,O.; Dolgoshein,B.A.; Kantserov,V.A.; Krasnopevtsev,D.; Romaniouk,A.; Shulga,E; Smirnov,S.Y.; Smirnov,Y.; Soldatov,E.Y.; Timoshenko,S.; Vorobev,K; // Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 2017. - 765. - с. 32-52

Annotation:

A search is presented for new resonances decaying to a W or Z boson and a Higgs boson in the ℓ+bb¯, ℓνbb¯, and νν¯bb¯ channels in pp collisions at s=13 TeV with the ATLAS detector at the Large Hadron Collider using a total integrated luminosity of 3.2 fb−1. The search is conducted by looking for a localized excess in the WH/ZH invariant or transverse mass distribution. No significant excess is observed, and the results are interpreted in terms of constraints on a simplified model based on a phenomenological Lagrangian of heavy vector triplets. © 2016 The Author(s)

Search for lepton-flavour-violating decays of the Higgs and Z bosons with the ATLAS detector / Antonov,A.; Belotskiy,K.; Belyaev,N.L.; Bulekov,O.; Dolgoshein,BA; Kantserov,V.A.; Krasnopevtsev,D.; Romaniouk,A.; Shulga,E; Smirnov,S.Y.; Smirnov,Y.; Soldatov,E.Y.; Tikhomirov,V.O; Timoshenko,S.; Vorobev,K; // European Physical Journal C. - 2017. - 77. - с.

Annotation:

Direct searches for lepton flavour violation in decays of the Higgs and Z bosons with the ATLAS detector at the LHC are presented. The following three decays are considered: H→ eτ, H→ μτ, and Z→ μτ. The searches are based on the data sample of proton–proton collisions collected by the ATLAS detector corresponding to an integrated luminosity of 20.3 fb - 1 at a centre-of-mass energy of s=8 TeV. No significant excess is observed, and upper limits on the lepton-flavour-violating branching ratios are set at the 95% confidence level: Br(H→ eτ) < 1.04 % , Br(H→ μτ) < 1.43 % , and Br(Z→ μτ) < 1.69 × 10 - 5. © 2017, CERN for the benefit of the ATLAS collaboration.

Measurement of the prompt J/ ψ pair production cross-section in pp collisions at √s=8 TeV with the ATLAS detector / Antonov,A.; Belotskiy,K.; Belyaev,N.L.; Bulekov,O.; Kantserov,V.A.; Krasnopevtsev,D.; Romaniouk,A.; Shulga,E; Smirnov,S.Y.; Smirnov,Y.; Soldatov,E.Y.; Tikhomirov,V.O; Timoshenko,S.; Vorobev,K; // European Physical Journal C. - 2017. - 77. - с.

Annotation:

The production of two prompt J/ ψ mesons, each with transverse momenta pT> 8.5 GeV and rapidity |y| < 2.1 , is studied using a sample of proton-proton collisions at s=8 TeV, corresponding to an integrated luminosity of 11.4 fb- 1 collected in 2012 with the ATLAS detector at the LHC. The differential cross-section, assuming unpolarised J/ ψ production, is measured as a function of the transverse momentum of the lower-pTJ/ ψ meson, di-J/ ψpT and mass, the difference in rapidity between the two J/ ψ mesons, and the azimuthal angle between the two J/ ψ mesons. The fraction of prompt pair events due to double parton scattering is determined by studying kinematic correlations between the two J/ ψ mesons. The total and double parton scattering cross-sections are compared with predictions. The effective cross-section of double parton scattering is measured to be σeff= 6.3 ± 1.6 (stat) ± 1.0 (syst) mb. © 2017, CERN for the benefit of the ATLAS collaboration.

Measurement of W boson angular distributions in events with high transverse momentum jets at s=8 TeV using the ATLAS detector / Antonov,A.; Belotskiy,K.; Belyaev,N.L.; Bulekov,O.; Kantserov,V.A.; Krasnopevtsev,D.; Romaniouk,A.; Shulga,E; Smirnov,S.Y.; Smirnov,Y.; Soldatov,E.Y.; Timoshenko,S.; Vorobev,K; // Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 2017. - 765. - с. 132-153

Annotation:

The W boson angular distribution in events with high transverse momentum jets is measured using data collected by the ATLAS experiment from proton–proton collisions at a centre-of-mass energy s=8 TeV at the Large Hadron Collider, corresponding to an integrated luminosity of 20.3 fb−1. The focus is on the contributions to W+jets processes from real W emission, which is achieved by studying events where a muon is observed close to a high transverse momentum jet. At small angular separations, these contributions are expected to be large. Various theoretical models of this process are compared to the data in terms of the absolute cross-section and the angular distributions of the muon from the leptonic W decay. © 2016 / Antonov,A.; Belotskiy,K.; Belyaev,N.L.; Bulekov,O.; Kantserov,V.A.; Krasnopevtsev,D.; Romaniouk,A.; Shulga,E; Smirnov,S.Y.; Smirnov,Y.; Soldatov,E.Y.; Timoshenko,S.; Vorobev,K; // Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 2017. - 765. - с. 132-153

Search for dark matter in association with a Higgs boson decaying to b-quarks in pp collisions at s=13 TeV with the ATLAS detector / Antonov,A.; Belotskiy,K.; Belyaev,N.L; Bulekov,O.; Dolgoshein,B.A.; Kantserov,V.A.; Krasnopevtsev,D.; Romaniouk,A.; Shulga,E; Smirnov,S.Y.; Smirnov,Y.; Soldatov,E.Y.; Timoshenko,S.; Vorobev,K; // Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 2017. - 765. - с. 11-31

Annotation:

A search for dark matter pair production in association with a Higgs boson decaying to a pair of bottom quarks is presented, using 3.2 fb−1 of pp collisions at a centre-of-mass energy of 13 TeV collected by the ATLAS detector at the LHC. The decay of the Higgs boson is reconstructed as a high-momentum bb¯ system with either a pair of small-radius jets, or a single large-radius jet with substructure. The observed data are found to be consistent with the expected backgrounds. Results are interpreted using a simplified model with a Z gauge boson mediating the interaction between dark matter and the Standard Model as well as a two-Higgs-doublet model containing an additional Z boson which decays to a Standard Model Higgs boson and a new pseudoscalar Higgs boson, the latter decaying into a pair of dark matter particles. © 2016 The Author(s)

The wide-aperture gamma-ray telescope TAIGA-HiSCORE in the Tunka Valley: Design, composition and commissioning / Astapov,I.; Bogdanov,A.; Kokoulin,R.; Komponiest,K.; Petrukhin,A.; Yashin,I.; // Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment. - 2017. - 845. - с. 367-372

Annotation:

The new TAIGA-HiSCORE non-imaging Cherenkov array aims to detect air showers induced by gamma rays above 30 TeV and to study cosmic rays above 100 TeV. TAIGA-HiSCORE is made of integrating air Cherenkov detector stations with a wide field of view (0.6), placed at a distance of about 100 m. They cover an area of initially 0.25km (prototype array), and of 5km at the final phase of the experiment. Each station includes 4 PMTs with 20 or 25 cm diameter, equipped with light guides shaped as Winstone cones. We describe the design, specifications of the read-out, DAQ and control and monitoring systems of the array. The present 28 detector stations of the TAIGA-HiSCORE engineering setup are in operation since September 2015. © 2016 Elsevier B.V.

Pulsational Pair-instability Model for Superluminous Supernova PTF12dam:Interaction and Radioactive Decay / Baklanov,P.; // Astrophysical Journal. - 2017. - 835. - с.

Annotation:

Being a superluminous supernova, PTF12dam can be explained by a 56Ni-powered model, a magnetar-powered model, or an interaction model. We propose that PTF12dam is a pulsational pair-instability supernova, where the outer envelope of a progenitor is ejected during the pulsations. Thus, it is powered by a double energy source: radioactive decay of 56Ni and a radiative shock in a dense circumstellar medium. To describe multicolor light curves and spectra, we use radiation-hydrodynamics calculations of the STELLA code. We found that light curves are well described in the model with 40 Mo ejecta and 20-40 Mo circumstellar medium. The ejected 56Ni mass is about 6 Mo, which results from explosive nucleosynthesis with large explosion energy (2-3) × 1052 erg. In comparison with alternative scenarios of pair-instability supernova and magnetar-powered supernova, in the interaction model, all the observed main photometric characteristics are well reproduced: multicolor light curves, color temperatures, and photospheric velocities. © 2017. The American Astronomical Society. All rights reserved.

Charged-particle multiplicities in proton–proton collisions at √s=0.9 to 8 TeV / Belyaev,V.; Bogdanov,A.; Grigoriev,V.; Ippolitov,M.; Kaplin,V.; Kondratyeva,N.; Loginov,V.; Melikyan,Y.; Peresunko,D.; // European Physical Journal C. - 2017. - 77. - с.

Annotation:

A detailed study of pseudorapidity densities and multiplicity distributions of primary charged particles produced in proton–proton collisions, at s= 0.9, 2.36, 2.76, 7 and 8 TeV, in the pseudorapidity range | η| < 2 , was carried out using the ALICE detector. Measurements were obtained for three event classes: inelastic, non-single diffractive and events with at least one charged particle in the pseudorapidity interval | η| < 1. The use of an improved track-counting algorithm combined with ALICE’s measurements of diffractive processes allows a higher precision compared to our previous publications. A KNO scaling study was performed in the pseudorapidity intervals | η| < 0.5, 1.0 and 1.5. The data are compared to other experimental results and to models as implemented in Monte Carlo event generators PHOJET and recent tunes of PYTHIA6, PYTHIA8 and EPOS. © 2017, CERN for the benefit of the ALICE collaboration.

J/ψ suppression at forward rapidity in Pb–Pb collisions at sNN=5.02 TeV / Belyaev,V.; Bogdanov,A.; Grigoriev,V.; Ippolitov,M.; Kaplin,V.; Kondratyeva,N.; Loginov,V.; Melikyan,Y.; Peresunko,D.; Samsonov,V.; // Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 2017. - 766. - с. 212-224

Annotation:

The inclusive J/ψ production has been studied in Pb–Pb and pp collisions at the centre-of-mass energy per nucleon pair sNN=5.02 TeV, using the ALICE detector at the CERN LHC. The J/ψ meson is reconstructed, in the centre-of-mass rapidity interval 2.5>y<4 and in the transverse-momentum range pT<12 GeV/c, via its decay to a muon pair. In this Letter, we present results on the inclusive J/ψ cross section in pp collisions at s=5.02 TeV and on the nuclear modification factor RAA. The latter is presented as a function of the centrality of the collision and, for central collisions, as a function of the transverse momentum pT of the J/ψ. The measured RAA values indicate a suppression of the J/ψ in nuclear collisions and are then compared to our previous results obtained in Pb–Pb collisions at sNN=2.76 TeV. The ratio of the RAA values at the two energies is also computed and compared to calculations of statistical and dynamical models. The numerical value of the ratio for central events (0–10% centrality) is 1.17±0.04(stat)±0.20(syst). In central events, as a function of pT, a slight increase of RAA with collision energy is visible in the region 2<pT<6 GeV/c. Theoretical calculations qualitatively describe the measurements, within uncertainties. © 2017 The Author

Measurement of the 2 nu beta beta decay half-life and search for the 0 nu beta beta decay of Cd-116 with the NEMO-3 detector / Brudanin,V; // PHYSICAL REVIEW D. - 2017. - 95. - с.

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The NEMO-3 experiment measured the half-life of the 2 nu beta beta decay and searched for the 0 nu beta beta decay of Cd-116. Using 410 g of Cd-116 installed in the detector with an exposure of 5.26 y, (4968 +/- 74) events corresponding to the 2 nu beta beta decay of Cd-116 to the ground state of Sn-116 have been observed with a signal to background ratio of about 12. The half-life of the 2 nu beta beta decay has been measured to be T-1/2(2 nu) = [2.74 +/- 0.04(stat) +/- 0.18(syst)] x 10(19) y. No events have been observed above the expected background while searching for 0 nu beta beta decay. The corresponding limit on the half-life is determined to be T-1/2(0 nu) >= 1.0 x 10(23) y at the 90% C. L. which corresponds to an upper limit on the effective Majorana neutrino mass of < m(nu)> <= 1.4-2.5 eV depending on the nuclear matrix elements considered. Limits on other mechanisms generating 0 nu beta beta decay such as the exchange of R-parity violating supersymmetric particles, right-handed currents and majoron emission are also obtained.

Measurements of the tt¯ production cross section in lepton+jets final states in pp collisions at 8 TeV and ratio of 8 to 7 TeV cross sections / Bylinkin,A.; Matveev,V.; Azarkin,M.; Dremin,I.; Leonidov,A.; // European Physical Journal C. - 2017. - 77. - с.

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A measurement of the top quark pair production (tt¯) cross section in proton–proton collisions at the centre-of-mass energy of 8TeV is presented using data collected with the CMS detector at the LHC, corresponding to an integrated luminosity of 19.6fb-1. This analysis is performed in the tt¯ decay channels with one isolated, high transverse momentum electron or muon and at least four jets, at least one of which is required to be identified as originating from hadronization of a b quark. The calibration of the jet energy scale and the efficiency of b jet identification are determined from data. The measured tt¯ cross section is 228.5±3.8(stat)±13.7(syst)±6.0(lumi) pb. This measurement is compared with an analysis of 7TeV data, corresponding to an integrated luminosity of 5.0fb-1, to determine the ratio of 8TeV to 7TeV cross sections, which is found to be 1.43±0.04(stat)±0.07(syst)±0.05(lumi). The measurements are in agreement with QCD predictions up to next-to-next-to-leading order. © 2017, CERN for the benefit of the CMS collaboration.

Evidence for collectivity in pp collisions at the LHC / Chadeeva,M.; Chistov,R.; Rusinov,V.; // Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 2017. - 765. - с. 193-220

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Measurements of two- and multi-particle angular correlations in pp collisions at s=5,7, and 13TeV are presented as a function of charged-particle multiplicity. The data, corresponding to integrated luminosities of 1.0pb−1 (5 TeV), 6.2pb−1 (7 TeV), and 0.7pb−1 (13 TeV), were collected using the CMS detector at the LHC. The second-order (v2) and third-order (v3) azimuthal anisotropy harmonics of unidentified charged particles, as well as v2 of KS 0 and Λ/Λ‾ particles, are extracted from long-range two-particle correlations as functions of particle multiplicity and transverse momentum. For high-multiplicity pp events, a mass ordering is observed for the v2 values of charged hadrons (mostly pions), KS 0, and Λ/Λ‾, with lighter particle species exhibiting a stronger azimuthal anisotropy signal below pT≈2GeV/c. For 13 TeV data, the v2 signals are also extracted from four- and six-particle correlations for the first time in pp collisions, with comparable magnitude to those from two-particle correlations. These observations are similar to those seen in pPb and PbPb collisions, and support the interpretation of a collective origin for the observed long-range correlations in high-multiplicity pp collisions. © 2016 The Author

Measurement of the WZ production cross section in pp collisions at s=13 TeV / Chadeeva,M.; Danilov,M.; Markin,O.; // Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 2017. - 766. - с. 268-290

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The WZ production cross section in proton–proton collisions at s=13 TeV is measured with the CMS experiment at the LHC using a data sample corresponding to an integrated luminosity of 2.3 fb−1. The measurement is performed in the leptonic decay modes WZ→ℓνℓ, where ℓ,ℓ=e,μ. The measured cross section for the range 60<mℓ′ℓ′<120 GeV is σ(pp→WZ)=39.9±3.2(stat) (syst)−3.1+2.9±0.4(theo)±1.3(lumi) pb, consistent with the standard model prediction. © 2017 The Author(s)

Search for the 0(--) glueball in Upsilon(1S) and Upsilon(2S) decays / Chilikin,K.; Mizuk,R.; Zhukova,V; // PHYSICAL REVIEW D. - 2017. - 95. - с.

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We report the first search for the J(PC) = 0(--) glueball in Upsilon(1S) and Upsilon(2S) decays with data samples of (102 +/- 2) x 10(6) and (158 +/- 4) x 10(6) events, respectively, collected with the Belle detector. No significant signals are observed in any of the proposed production modes, and the 90% credibility level upper limits on their branching fractions in Upsilon(1S) and Upsilon(2S) decays are obtained. The inclusive branching fractions of the Upsilon(1S) and Upsilon(2S) decays into final states with chi(c1) are measured to be B(Upsilon(1S) -> chi(c1) + anything) = (1.90 +/- 0.43(stat) +/- 0.14(syst) x 10(-4) with an improved precision over prior measurements and B Upsilon(2S) -> chi(c1) + anything) = (2.24 +/- 0.44(stat) +/- 0.20(syst) x 10(-4) for the first time.

Observation of the decay B+ → ψ(2S)ϕ(1020)K+ in pp collisions at s=8TeV / Chistov,R.; Danilov,M.; Rusinov,V.; // Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 2017. - 764. - с. 66-86

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The decay B+→ψ(2S)ϕ(1020)K+ is observed for the first time using data collected from pp collisions at s=8TeV by the CMS experiment at the LHC, corresponding to an integrated luminosity of 19.6fb−1. The branching fraction of this decay is measured, using the mode B+→ψ(2S)K+ as normalization, to be (4.0±0.4(stat)±0.6(syst)±0.2(B))×10−6, where the third uncertainty is from the measured branching fraction of the normalization channel. © 2016 The Author(s)

Observation of D0 →ρ0γ and Search for CP Violation in Radiative Charm Decays / Chistov,R.; Mizuk,R.; Pakhlov,P.; Zhukova,V.; // Physical Review Letters. - 2017. - 118. - с.

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We report the first observation of the radiative charm decay D0→ρ0γ and the first search for CP violation in decays D0→ρ0γ, φγ, and K̄∗0(892)γ, using a data sample of 943 fb-1 collected with the Belle detector at the KEKB asymmetric-energy e+e- collider. The branching fraction is measured to be B(D0→ρ0γ)=(1.77±0.30±0.07)×10-5, where the first uncertainty is statistical and the second is systematic. The obtained CP asymmetries ACP(D0→ρ0γ)=+0.056±0.152±0.006, ACP(D0→φγ)=-0.094±0.066±0.001, and ACP(D0→K̄∗0γ)=-0.003±0.020±0.000 are consistent with no CP violation. We also present an improved measurement of the branching fractions B(D0→φγ)=(2.76±0.19±0.10)×10-5 and B(D0→K̄∗0γ)=(4.66±0.21±0.21)×10-4. © 2017 American Ph

Effect of self-ion irradiation on the microstructural changes of alloy EK-181 in annealed and severely deformed conditions / Dzhumaev,P.S.; Emelyanova,O.V.; Ganchenkova,M.G.; Kalin,B.A.; Leontiva-Smirnova,M.; Garner,F.A.; // Journal of Nuclear Materials. - 2017. - 487. - с. 96-104

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EK-181 is a low-activation ferritic/martensitic steel that is an attractive candidate for in-core component materials for both fast reactors and fusion reactors. To assess the effect of microstructural engineering on radiation response, two variants of EK-181 were studied: one in an annealed condition and the other subject to severe plastic deformation. These specimens were irradiated with 3.5 MeV Fe self-ions up to 400 peak displacements per atom (dpa) at temperatures ranging from 400 °C to 500 °C. The deformation did not suppress swelling over the whole irradiated region. Instead, deformed samples showed higher swelling in the near-surface region. Void swelling was found to be correlated with grain boundary instability. Significant grain growth occurred when steady-state void growth started. © 2017 Elsevier B.V.

Study of the flux effect nature for vver-1000 RPV welds with high nickel content / Kuleshova,E.A.; // Journal of Nuclear Materials. - 2017. - 483. - с. 1-12

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This work extends the research of the basic regularities of segregation processes in the grain boundaries (GB) of VVER-1000 reactor pressure vessel (RPV) steels. The paper considers the influence of irradiation with different fast neutron fluxes on the structure, yield strength and ductile-to-brittle transition temperature (TK) changes as well as on changes of the share of brittle intergranular fracture and development of segregation processes in the VVER-1000 RPV weld metal (WM). The obtained experimental results allow to separate the contribution of the hardening and non-hardening mechanisms to mechanical properties degradation of material irradiated at the operating temperature. It is shown that the difference in TK shift in WM irradiated to the same fluence with different fast neutron fluxes is mainly due to the difference in the GB accumulation kinetics of impurities and only to a small extent due to the material hardening. Phosphorus bulk diffusion coefficients were evaluated for the temperature exposure, accelerated irradiation and irradiation within surveillance specimens (SS) using a kinetic model of phosphorus GB accumulation in low-alloyed low-carbon steels under the influence of operational factors. The correlation between the GB segregation level of phosphorus and nickel, and the TK shift - in WM SS was obtained experimentally and indicates the non-hardening mechanism contribution to the total radiation embrittlement of VVER-1000 RPV steels throughout its extended lifetime. © 2016 Elsevier B.V.

Generalized polarizabilities of the nucleon in baryon chiral perturbation theory / Lensky,V.; // European Physical Journal C. - 2017. - 77. - с.

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The nucleon generalized polarizabilities (GPs), probed in virtual Compton scattering (VCS), describe the spatial distribution of the polarization density in a nucleon. They are accessed experimentally via the process of electron–proton bremsstrahlung (ep→ epγ) at electron-beam facilities, such as MIT-Bates, CEBAF (Jefferson Lab), and MAMI (Mainz). We present the calculation of the nucleon GPs and VCS observables at next-to-leading order in baryon chiral perturbation theory (BχPT), and confront the results with the empirical information. At this order our results are predictions, in the sense that all the parameters are well known from elsewhere. Within the relatively large uncertainties of our calculation we find good agreement with the experimental observations of VCS and the empirical extractions of the GPs. We find large discrepancies with previous chiral calculations – all done in heavy-baryon χPT (HBχPT) – and discuss the differences between BχPT and HBχPT responsible for these discrepancies. © 2017, The Author(s).

Effect of low electric fields on alpha scintillation light yield in liquid argon / Machulin,I.N.; Skorokhvatov,M.D.; // Journal of Instrumentation. - 2017. - 12. - с.

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Measurements were made of scintillation light yield of alpha particles from the 222Rn decay chain within the DarkSide-50 liquid argon time projection chamber. The light yield was found to increase as the applied electric field increased, with alphas in a 200 V/cm electric field exhibiting a ∼2% increase in light yield compared to alphas in no field. © 2017 IOP Publishing Ltd and Sissa Medialab srl.

Search for Dark Matter and Supersymmetry with a Compressed Mass Spectrum in the Vector Boson Fusion Topology in Proton-Proton Collisions at s =8 TeV / Matveev,V.; Chistov,R.; Danilov,M.; Rusinov,V.; Azarkin,M.; Dremin,I.; Leonidov,A.; // Physical Review Letters. - 2017. - 118. - с.

Annotation:

A first search for pair production of dark matter candidates through vector boson fusion in proton-proton collisions at s=8 TeV is performed with the CMS detector. The vector boson fusion topology enhances missing transverse momentum, providing a way to probe supersymmetry, even in the case of a compressed mass spectrum. The data sample corresponds to an integrated luminosity of 18.5 fb-1, recorded by the CMS experiment. The observed dijet mass spectrum is consistent with the standard model expectation. In an effective field theory, dark matter masses are explored as a function of contact interaction strength. The most stringent limit on bottom squark production with mass below 315 GeV is also reported, assuming a 5 GeV mass difference with respect to the lightest neutralino. © 2017 CERN, for the CMS Collaboration. Published by the American Physical Society under the terms of the «https://creativecommons.org/licenses/by/4.0/» Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.

Tabulating knot polynomials for arborescent knots / Mironov,A.; Morozov,A.; Morozov,A.; Sleptsov,A.; // Journal of Physics A: Mathematical and Theoretical. - 2017. - 50. - с.

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Arborescent knots are those which can be represented in terms of double fat graphs or equivalently as tree Feynman diagrams. This is the class of knots for which the present knowledge is sufficient for lifting topological description to the level of effective analytical formulas. The paper describes the origin and structure of the new tables of colored knot polynomials, which will be posted at the dedicated site (http://knotebook.org). Even if formal expressions are known in terms of modular transformation matrices, the computation in finite time requires additional ideas. We use the 'family' approach, suggested in Mironov and Morozov (2015 Nucl. Phys. B 899 395-413), and apply it to arborescent knots in the Rolfsen table by developing a Feynman diagram technique, associated with an auxiliary matrix model field theory. Gauge invariance in this theory helps to provide meaning to Racah matrices in the case of non-trivial multiplicities and explains the need for peculiar sign prescriptions in the calculation of [21]-colored HOMFLY-PT polynomials. © 2017 IOP Publishing Ltd.

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On moduli space of symmetric orthogonal matrices and exclusive Racah matrix S¯ for representation R = [3,1] with multiplicities / Morozov,A.; // Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 2017. - 766. - с. 291-300

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Racah matrices and higher j-symbols are used in description of braiding properties of conformal blocks and in construction of knot polynomials. However, in complicated cases the logic is actually inverted: they are much better deduced from these applications than from the basic representation theory. Following the recent proposal of [1] we obtain the exclusive Racah matrix S¯ for the currently-front-line case of representation R=[3,1] with non-trivial multiplicities, where it is actually operator-valued, i.e. depends on the choice of bases in the intertwiner spaces. Effective field theory for arborescent knots in this case possesses gauge invariance, which is not yet properly described and understood. Because of this lack of knowledge a big part (about a half) of S¯ needs to be reconstructed from orthogonality conditions. Therefore we discuss the abundance of symmetric orthogonal matrices, to which S¯ belongs, and explain that dimension of their moduli space is also about a half of that for the ordinary orthogonal matrices. Thus the knowledge approximately matches the freedom and this explains why the method can work – with some limited addition of educated guesses. A similar calculation for R=[r,1] for r>3 should also be doable. © 2017 The Author(s)

Search for sterile neutrinos in muon neutrino disappearance mode at FNAL / Polukhina,N.; // European Physical Journal C. - 2017. - 77. - с.

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The NESSiE Collaboration has been setup to undertake a conclusive experiment to clarify the muon-neutrino disappearance measurements at short baselines in order to put severe constraints to models with more than the three-standard neutrinos. To this aim the current FNAL-Booster neutrino beam for a Short-Baseline experiment was carefully evaluated by considering the use of magnetic spectrometers at two sites, near and far ones. The detector locations were studied, together with the achievable performances of two OPERA-like spectrometers. The study was constrained by the availability of existing hardware and a time-schedule compatible with the undergoing project of multi-site Liquid–Argon detectors at FNAL. The settled physics case and the kind of proposed experiment on the Booster neutrino beam would definitively clarify the existing tension between the νμ disappearance and the νe appearance/disappearance at the eV mass scale. In the context of neutrino oscillations the measurement of νμ disappearance is a robust and fast approach to either reject or discover new neutrino states at the eV mass scale. We discuss an experimental program able to extend by more than one order of magnitude (for neutrino disappearance) and by almost one order of magnitude (for antineutrino disappearance) the present range of sensitivity for the mixing angle between standard and sterile neutrinos. These extensions are larger than those achieved in any other proposal presented so far. © 2017, The Author(s).

Epitaxial growth of mosaic diamond: Mapping of stress and defects in crystal junction with a confocal Raman spectroscopy / Ralchenko,V.G.; Khomich,A.A.; Ashkinazi,E.E.; Bolshakov,A.P.; // Journal of Crystal Growth. - 2017. - 463. - с. 19-26

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We studied defects and stress distributions in mosaic epitaxial diamond film using a confocal Raman spectroscopy, with a special attention to the junction area between the crystals. The mosaics was grown by microwave plasma CVD on closely arranged (1 0 0)-oriented HPHT type Ib substrates. The width of stress affected and defect enriched region around the junction show a tendency of extending with the film thickness, from ≈40 μm on the film-substrate interface to ≈250 μm in the layer 500 μm above the substrate, as found from the mosaics analysis in cross-section. The stress field around the junction demonstrates a complex pattern, with mixed domains of tensile and compressive stress, with maximum value of σ ≈ 0.6 GPa. A similar non-uniform pattern was observed for defect distribution as well. No sign of amorphous sp2 carbon in the junction zone was revealed. © 2017

Axial anomaly and energy dependence of hyperon polarization in heavy-ion collisions / Sorin,A.; Teryaev,O.; // Physical Review C - Nuclear Physics. - 2017. - 95. - с.

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We address the issue of energy and charge dependence of global polarization of Λ hyperons in peripheral Au-Au collisions recently observed by the STAR Collaboration at Relativistic Heavy Ion Collider (RHIC). We compare different contributions to the anomalous mechanism relating polarization to vorticity and hydrodynamic helicity in QCD matter. We stress that the suppression of the gravitational anomaly contribution in strongly correlated matter observed in lattice simulations confirms our earlier prediction of rapid decrease of polarization with increasing collision energy. Our mechanism leads to polarization of Λ of the same sign and larger magnitude than the polarization of Λ. The energy and charge dependence of polarization is suggested as a sensitive probe of fine details of QCD matter structure. © 2017 American Physical Society.

Express in situ measurement of epitaxial CVD diamond film growth kinetics / Yurov,V.Y.; Bolshakov,A.; Ralchenko,V.; Khomich,A.A.; Antonova,I.A.; Ashkinazi,E.E.; Shershulin,V.A.; Konov,V.; // Diamond and Related Materials. - 2017. - 72. - с. 61-70

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We used a low-coherence interferometry for precise continuous in situ measurements of thickness and growth rate of epitaxial single crystal diamond layers in microwave plasma CVD in H2-CH4 gas mixtures in a broad range of substrate temperatures Ts (750–1150 °C) and CH4 concentrations (1–13%). Rich growth kinetics is collected in a single experiment by depositing about 60 layers on one (100) Ib HPHT diamond substrate in different regimes (the substrate temperature was controlled by the microwave power) at fixed pressure P = 130 Torr, without the plasma switch-off. The growth rate is found to follow Arrhenius dependence with activation energy Ea = 11.1 ± 1.0 kcal/mol. By appropriate choice of the substrate temperature the growth rate can be significantly enhanced. The growth rate as high as 82 μm/h is achieved by optimizing the temperature and gas composition. At low CH4 content (1%) growth competes with etching by atomic hydrogen, the etching dominating at high Ts (> 1000 °C in the present conditions). The etching rate in pure H2 plasma was measured and activation energy Ea = 9.8 ± 0.8 kcal/mol was deduced. Gas temperature Tg in the plasma core evaluated from optical emission spectra for dimer C2 (Swan band), was found to be either constant or slightly and monotonically increasing with absorbed power, whereas the absorbed microwave power density shows a decreasing, although slight, trend. This suggests the temperature depended surface reactions to play a major role in the diamond growth kinetics under variable microwave power. Raman mapping of cross-section of the produced multilayered sample confirmed high quality of diamond structure over all the deposition regimes explored. © 2017 Elsevier B.V.

Measurement of the ZZ production cross section in proton-proton collisions at √s=8 TeV using the ZZ → ℓ−ℓ+ℓ′−ℓ′+ and ZZ→ ℓ−ℓ+νν¯ decay channels with the ATLAS detector / Antonov,A.; Belotskiy,K.; Belyaev,N.L.; Bulekov,O.; Kantserov,V.A.; Krasnopevtsev,D.; Romaniouk,A.; Shulga,E; Smirnov,S.Y.; Smirnov,Y.; Soldatov,E.Y.; Tikhomirov,V.O; Timoshenko,S.; Vorobev,K; // Journal of High Energy Physics. - 2017. - 2017. - с.

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A measurement of the ZZ production cross section in the ℓ+′ −′ + and ℓ+νν¯ channels (ℓ = e, μ) in proton-proton collisions at s=8TeV at the Large Hadron Collider at CERN, using data corresponding to an integrated luminosity of 20.3 fb−1 collected by the ATLAS experiment in 2012 is presented. The fiducial cross sections for ZZ → ℓ+′ −′ + and ZZ→ ℓ+νν¯ are measured in selected phase-space regions. The total cross section for ZZ events produced with both Z bosons in the mass range 66 to 116 GeV is measured from the combination of the two channels to be 7.3 ± 0.4(stat) ± 0.3(syst)− 0.1 − 0.2(lumi) pb, which is consistent with the Standard Model prediction of 6. 6− 0.6 + 0.7 pb. The differential cross sections in bins of various kinematic variables are presented. The differential event yield as a function of the transverse momentum of the leading Z boson is used to set limits on anomalous neutral triple gauge boson couplings in ZZ production.[Figure not available: see fulltext.] © 2017, The Author(s).

Measurements of ψ(2S) and X(3872) → J/ψπ + π − production in pp collisions at √s=8 TeV with the ATLAS detector / Antonov,A.; Belotskiy,K.; Belyaev,N.L.; Bulekov,O.; Kantserov,V.A.; Krasnopevtsev,D.; Romaniouk,A.; Shulga,E; Smirnov,S.Y.; Smirnov,Y.; Soldatov,E.Y.; Tikhomirov,V.O; Timoshenko,S.; Vorobev,K; // Journal of High Energy Physics. - 2017. - 2017. - с.

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Differential cross sections are presented for the prompt and non-prompt production of the hidden-charm states X(3872) and ψ(2S), in the decay mode J/ψπ+π, measured using 11.4 fb−1 of pp collisions at s=8 TeV by the ATLAS detector at the LHC. The ratio of cross-sections X(3872)/ψ(2S) is also given, separately for prompt and non-prompt components, as well as the non-prompt fractions of X(3872) and ψ(2S). Assuming independent single effective lifetimes for non-prompt X(3872) and ψ(2S) production gives RB=ℬ(B→X(3872)+any)ℬ(X(3872)→J/ψπ+π−)/ℬ(B→ψ(2S)+any)ℬ(ψ(2S)→J/ψπ+π−)=(3.95±0.32(stat)±0.08(sys))×10−2 separating short- and long-lived contributions, assuming that the short-lived component is due to Bc decays, gives RB = (3.57 ± 0.33(stat) ± 0.11(sys)) × 10−2, with the fraction of non-prompt X(3872) produced via Bc decays for pT(X(3872)) > 10 GeV being (25 ± 13(stat) ± 2(sys) ± 5(spin))%. The distributions of the dipion invariant mass in the X(3872) and ψ(2S) decays are also measured and compared to theoretical predictions.[Figure not available: see fulltext.] © 2017, The Author(s).

Effect of hydrogen peroxide on crack growth rate in X70 pipeline steel in weak acid solution / Bachurina,D.; // Corrosion Engineering Science and Technology. - 2017. - . - с. 1-8

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An investigation of the effect of hydrogen peroxide (H2O2) on corrosion crack growth can be considered as a necessary stage in a study of the SCC of pipeline steels in the presence of dissolved oxygen and other oxidants. It was found that the presence of hydrogen peroxide at a low concentration (5 mM) results in a deceleration of the crack growth. With an increase in the concentration of H2O2, the crack growth rate increases. The change in the steel corrosion rate at various H2O2 concentrations agrees with the dependence of the crack growth rate on the oxidant concentration. The conclusion has been made that the crack growth in a weakly acidic electrolyte (pH 5.5) is determined by the metal dissolution process. Hydrogen charging of the metal indirectly affects the crack growth by increasing the surface coverage with hydrogen, which decreases the steel dissolution rate. © 2017 Institute of Materials, Minerals and Mining Published by Taylor & Francis on behalf of the Institute

W and Z boson production in p-Pb collisions at √sNN=5.02 TeV / Belyaev,V.; Bogdanov,A.; Grigoriev,V.; Ippolitov,M.; Kaplin,V.; Kondratyeva,N.; Loginov,V.; Melikyan,Y.; Peresunko,D.; Samsonov,V.; // Journal of High Energy Physics. - 2017. - 2017. - с.

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The W and Z boson production was measured via the muonic decay channel in proton-lead collisions at sNN=5.02 TeV at the Large Hadron Collider with the ALICE detector. The measurement covers backward (−4.46 < ycms < −2.96) and forward (2.03 < ycms < 3.53) rapidity regions, corresponding to Pb-going and p-going directions, respectively. The Z-boson production cross section, with dimuon invariant mass of 60 < mμμ < 120 GeV/c2 and muon transverse momentum (pT μ) larger than 20 GeV/c, is measured. The production cross section and charge asymmetry of muons from W-boson decays with pT μ > 10 GeV/c are determined. The results are compared to theoretical calculations both with and without including the nuclear modification of the parton distribution functions. The W-boson production is also studied as a function of the collision centrality: the cross section of muons from W-boson decays is found to scale with the average number of binary nucleon-nucleon collisions within uncertainties.[Figure not available: see fulltext.] © 2017, The Author(s).

The effect of Al concentration on thermodynamic properties of Nd and U in Ga-Al-based alloys and the separation factor of Nd/U couple in a "molten salt-liquid metal system" / Bychkov,Alexander; // JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY. - 2017. - 311. - с. 687-693;

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Electrochemical behavior of neodymium and uranium in a molten Nd(U)-(Ga-xAl)/3LiCl-2KCl system (x = 1.5; 5.0 and 20.0 wt% Al) between 723 and 823 K was studied. Temperature dependencies of apparent standard potentials of Nd-(Ga-Al) and U-(Ga-Al) alloys were determined versus Cl-/Cl-2 reference electrode. Neodymium and uranium activity coefficients and Nd/U separation factor were calculated. Partial excess free Gibbs energy, partial enthalpy of mixing and partial excess entropy of Nd-(Ga-Al) and U-(Ga-Al) alloys were estimated.

Spatial structure of the modified Coulomb potential in a superstrong magnetic field / Glazyrin,S.I.; // JETP Letters. - 2017. - . - с. 1-5

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The modification of the Coulomb potential due to the enhancement of loop corrections in a superstrong magnetic field is studied numerically. We calculate the modified potential with high precision and obtain the pattern of equipotential lines. The results confirm the general features known from previous studies, however we emphasize some differences in potential structure that can be important for problems with spatially distributed charges. © 2017 Pleiades Publishing, Inc.

Device for remote control and monitoring of blood pressure / Khabibullin,T.R.; Lebedev,G.N.; Bulychev,I.G.; Tolstaya,A.; // International Journal of Tomography and Simulation. - 2017. - 30. - с. 21-30

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The paper proposes a device that allows to remotely carrying out daily monitoring of the patient’s blood pressure. The device is autonomous, uses oscillometric pressure measurement method with a stepwise pressure releasing and saving records of the pressure in the cuff. The authors describes the method of determining the blood pressure and the heart rate, as well as the data analysis algorithm, which was received by a device for daily monitoring of the blood pressure © 2017 by Ceser Publications.

Magnetic properties and defects of fe-ni-based magnetic microwires / Korchuganova,O.A.; Aleev,A.A.; // IEEE Transactions on Magnetics. - 2017. - 53. - с.

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We studied the magnetic properties and domain wall (DW) dynamics of Fe47.4Ni26.6Si11B13C2 and Fe77.5Si7.5B15 microwires. Both samples present a rectangular hysteresis loop and fast magnetization switching. The linear region of dependence of the DW velocity on the magnetic field in Fe47.4Ni26.6Si11B13C2 sample is considerably shorter. Consequently, we studied the structure of Fe47.4Ni26.6Si11B13C2 sample using X-ray diffraction and atom probe tomography. The results obtained using the atom probe tomography supports the formation of B-enriched precipitates in the interfacial layer and in the metallic nucleus after annealing. © 1965-2012 IEEE.

The efficiency of backward magnetic-pulse processing / Kudasov,Y.B.; Maslov,D.A.; Surdin,O.M.; // Technical Physics Letters. - 2017. - 43. - с. 92-94

Annotation:

The dependence of the efficiency of magnetic-pulse processing of materials on the pulsed magnetic-field shape has been studied. It is shown that, by using a pulse train instead of a single pulse in the fast-rising component of a magnetic field applied during the backward forming process, it is possible to increase the specific mechanical impulse transferred to a workpiece and, thus, improve the efficiency of processing. Possible applications of the proposed method to removing dents from car chassis and aircraft parts are considered © 2017, Pleiades Publishing, Ltd.

Borexino's search for low-energy neutrino and antineutrino signals correlated with gamma-ray bursts / Litvinovich,E.; Machulin,I.; Skorokhvatov,M.; // Astroparticle Physics. - 2017. - 86. - с. 11-17

Annotation:

A search for neutrino and antineutrino events correlated with 2350 gamma-ray bursts (GRBs) is performed with Borexino data collected between December 2007 and November 2015. No statistically significant excess over background is observed. We look for electron antineutrinos (ν¯e) that inverse beta decay on protons with energies from 1.8 MeV to 15 MeV and set the best limit on the neutrino fluence from GRBs below 8 MeV. The signals from neutrinos and antineutrinos from GRBs that scatter on electrons are also searched for, a detection channel made possible by the particularly radio-pure scintillator of Borexino. We obtain currently the best limits on the neutrino fluence of all flavors and species below 7 MeV. Finally, time correlations between GRBs and bursts of events are investigated. Our analysis combines two semi-independent data acquisition systems for the first time: the primary Borexino readout optimized for solar neutrino physics up to a few MeV, and a fast waveform digitizer system tuned for events above 1 MeV. © 2016 Elsevier B.V.

Search for high-mass Zγ resonances in e+e−γ and μ + μ −γ final states in proton-proton collisions at √s=8 and 13 TeV / Matveev,V.; Bylinkin,A.; Chadeeva,M.; Markin,O.; Tarkovskii,E.; Azarkin,M.; Dremin,I.; Leonidov,A.; // Journal of High Energy Physics. - 2017. - 2017. - с.

Annotation:

A search for neutrino and antineutrino events correlated with 2350 gamma-ray bursts (GRBs) is performed with Borexino data collected between December 2007 and November 2015. No statistically significant excess over background is observed. We look for electron antineutrinos (ν¯e) that inverse beta decay on protons with energies from 1.8 MeV to 15 MeV and set the best limit on the neutrino fluence from GRBs below 8 MeV. The signals from neutrinos and antineutrinos from GRBs that scatter on electrons are also searched for, a detection channel made possible by the particularly radio-pure scintillator of Borexino. We obtain currently the best limits on the neutrino fluence of all flavors and species below 7 MeV. Finally, time correlations between GRBs and bursts of events are investigated. Our analysis combines two semi-independent data acquisition systems for the first time: the primary Borexino readout optimized for solar neutrino physics up to a few MeV, and a fast waveform digitizer system tuned for events above 1 MeV. © 2016 Elsevier B.V.

Search for high-mass Zγ resonances in e+e−γ and μ + μ −γ final states in proton-proton collisions at √s=8 and 13 TeV / Matveev,V.; Bylinkin,A.; Chadeeva,M.; Markin,O.; Tarkovskii,E.; Azarkin,M.; Dremin,I.; Leonidov,A.; // Journal of High Energy Physics. - 2017. - 2017. - с.

Annotation:

This paper describes the search for a high-mass narrow-width scalar particle decaying into a Z boson and a photon. The analysis is performed using proton-proton collision data recorded with the CMS detector at the LHC at center-of-mass energies of 8 and 13 TeV, corresponding to integrated luminosities of 19.7 and 2.7 fb−1, respectively. The Z bosons are reconstructed from opposite-sign electron or muon pairs. No statistically significant deviation from the standard model predictions has been found in the 200-2000 GeV mass range. Upper limits at 95% confidence level have been derived on the product of the scalar particle production cross section and the branching fraction of the Z decaying into electrons or muons, which range from 280 to 20 fb for resonance masses between 200 and 2000 GeV.[Figure not available: see fulltext.] © 2017, The Author(s).

Search for heavy resonances decaying to tau lepton pairs in proton-proton collisions at √s=13 TeV / Matveev,V.; Bylinkin,A.; Chistov,R.; Danilov,M.; Rusinov,V.; Azarkin,M.; Dremin,I.; Leonidov,A.; // Journal of High Energy Physics. - 2017. - 2017. - с.

Annotation:

A search for heavy resonances that decay to tau lepton pairs is performed using proton-proton collisions at s=13 TeV. The data were collected with the CMS detector at the CERN LHC and correspond to an integrated luminosity of 2.2 fb−1. The observations are in agreement with standard model predictions. An upper limit at 95% confidence level on the product of the production cross section and branching fraction into tau lepton pairs is calculated as a function of the resonance mass. For the sequential standard model, the presence of Z′ bosons decaying into tau lepton pairs is excluded for Z′ masses below 2.1 TeV, extending previous limits for this final state. For the topcolor-assisted technicolor model, which predicts Z′ bosons that preferentially couple to third-generation fermions, Z′ masses below 1.7 TeV are excluded, representing the most stringent limit to date.[Figure not available: see fulltext.] © 2017, The Author(s).

Search for anomalous Wtb couplings and flavour-changing neutral currents in t-channel single top quark production in pp collisions at √s=7 and 8 TeV / Matveev,V.; Chadeeva,M.; Danilov,M.; Markin,O.; Azarkin,M.; Dremin,I.; Leonidov,A.; // Journal of High Energy Physics. - 2017. - 2017. - с.

Annotation:

Single top quark events produced in the t channel are used to set limits on anomalous Wtb couplings and to search for top quark flavour-changing neutral current (FCNC) interactions. The data taken with the CMS detector at the LHC in proton-proton collisions at s=7 and 8 TeV correspond to integrated luminosities of 5.0 and 19.7 fb−1, respectively. The analysis is performed using events with one muon and two or three jets. A Bayesian neural network technique is used to discriminate between the signal and backgrounds, which are observed to be consistent with the standard model prediction. The 95% confidence level (CL) exclusion limits on anomalous right-handed vector, and left- and right-handed tensor Wtb couplings are measured to be |fV R| < 0.16, |fT L| < 0.057, and − 0.049 < fT R < 0.048, respectively. For the FCNC couplings κtug and κtcg, the 95% CL upper limits on coupling strengths are |κtug|/Λ < 4.1 × 10− 3 TeV−1 and |κtcg|/Λ < 1.8 × 10− 2 TeV−1, where Λ is the scale for new physics, and correspond to upper limits on the branching fractions of 2.0 × 10−5 and 4.1 × 10−4 for the decays t → ug and t → cg, respectively.[Figure not available: see fulltext.] © 2017, The Author(s).

Measurement of the transverse momentum spectra of weak vector bosons produced in proton-proton collisions at √s=8 TeV / Matveev,V.; Chistov,R.; Danilov,M.; Markin,O.; Rusinov,V.; Tarkovskii,E.; Azarkin,M.; Dremin,I.; Leonidov,A.; // Journal of High Energy Physics. - 2017. - 2017. - с.

Annotation:

The transverse momentum spectra of weak vector bosons are measured in the CMS experiment at the LHC. The measurement uses a sample of proton-proton collisions at s=8 TeV, collected during a special low-luminosity running that corresponds to an integrated luminosity of 18.4 ± 0.5 pb−1. The production of W bosons is studied in both electron and muon decay modes, while the production of Z bosons is studied using only the dimuon decay channel. The ratios of W to W+ and Z to W differential cross sections are also measured. The measured differential cross sections and ratios are compared with theoretical predictions up to next-to-next leading order in QCD.[Figure not available: see fulltext.] © 2017, The Author(s).

Positron annihilation study of defects in copper irradiated with swift Xe26+ ions / Skuratov,V.A.; // Vacuum. - 2017. - 138. - с. 15-21

Annotation:

Variable energy positron beam and conventional positron lifetime spectroscopy were used to study pure copper exposed to irradiation with 167 MeV Xe26+ heavy ions with different doses of 1012, 1013, 5 × 1013, 1014 ions/cm2. The presence of vacancy-type defects induced by implantation was confirmed in Doppler spectroscopy characteristics. Decreasing of the positron diffusion length from 135 nm for unirradiated sample, to 82 nm for the lowest and to 46 nm for the highest applied dose was noted. It points out increasing defect concentration with the increase of the fluence. Additionally, the existence of one kind of defects in all irradiated samples was noticed. The defected zone covered with the implanted range and the so called “long range effect” was not confirmed. © 2017 Elsevier Ltd

Exclusive open-charm near-threshold cross sections in a coupled-channel approach / Uglov,T.V.; Kalashnikova,Y.S.; Nefediev,A.V.; Pakhlova,G.V.; Pakhlov,P.N.; // JETP Letters. - 2017. - . - с. 1-7

Annotation:

Data on open-charm channels collected by the Belle Collaboration are analysed simultaneously using a unitary approach based on a coupled-channel model in a wide energy range (Formula presented.). The resulting fit provides a remarkably good overall description of the line shapes in all studied channels. Parameters of 5 vector charmonium resonances are extracted from the fit. © 2016 Pleiades Publishing, Inc.

Restoring damaged JPEG images made by the wireless endoscopic capsule / Antonova,A.; Shayakov,A.; Khabibullin,T.; Tolstaya,A.; // International Journal of Imaging and Robotics. - 2017. - 17. - с. 108-118

Annotation:

The effectiveness of the software aimed at automated recognition of the pathologies and morphological changes of the digestive tract by the images obtained by the wireless endoscopic capsule depends on the pictures’ quality. This article deals with the algorithm for recovering the loss of the data from the part of the image code that encodes the picture itself, not the loss of metadata (supplementary information at the beginning of the entire code). The algorithm allows to reconstruct the images with shifted blocks by returning them to their original place and restoring their original colour. The algorithm was tested on 159 damaged images with different number of the breakdown and the experiment has restored about 90% of distorted frames. © 2017 [International Journal of Imaging and Robotics].

Fermi-LAT kills dark matter interpretations of AMS-02 data. Or not? / Belotsky,K.; Budaev,R.; Kirillov,A.; Laletin,M.; // Journal of Cosmology and Astroparticle Physics. - 2017. - 2017. - с.

Annotation:

A number of papers attempt to explain the positron anomaly in cosmic rays, observed by PAMELA and AMS-02, in terms of dark matter (DM) decays or annihilations. However, the recent progress in cosmic gamma-ray studies challenges these attempts. Indeed, as we show, any rational DM model explaining the positron anomaly abundantly produces final state radiation and Inverse Compton gamma rays, which inevitably leads to a contradiction with Fermi-LAT isotropic diffuse gamma-ray background measurements. Furthermore, the Fermi-LAT observation of Milky Way dwarf satellites, supposed to be rich in DM, revealed no significant signal in gamma rays. We propose a generic approach in which the major contribution to cosmic rays comes from the dark matter disc and prove that the tension between the DM origin of the positron anomaly and the cosmic gamma-ray observations can be relieved. We consider both a simple model, in which DM decay/annihilate into charged leptons, and a model-independent minimal case of particle production, and we estimate the optimal thickness of DM disk. Possible mechanisms of formation and its properties are briefly discussed. © 2017 IOP Publishing Ltd and Sissa Medialab srl.

Particle creation phenomenology, Dirac sea and the induced Weyl and Einstein-dilaton gravity / Dokuchaev,V.I.; // Journal of Cosmology and Astroparticle Physics. - 2017. - 2017. - с.

Annotation:

We constructed the conformally invariant model for scalar particle creation induced by strong gravitational fields. Starting from the "usual" hydrodynamical description of the particle motion written in the Eulerian coordinates we substituted the particle number conservation law (which enters the formalism) by "the particle creation law", proportional to the square of the Weyl tensor (following the famous result by Ya.B. Zel'dovich and A.A. Starobinsky). Then, demanding the conformal invariance of the whole dynamical system, we have got both the (Weyl)-conformal gravity and the Einstein-Hilbert gravity action integral with dilaton field. Thus, we obtained something like the induced gravity suggested first by A.D. Sakharov. It is shown that the resulting system is self-consistent. We considered also the vacuum equations. It is shown that, beside the "empty vacuum", there may exist the "dynamical vacuum", which is nothing more but the Dirac sea. The latter is described by the unexpectedly elegant equation which includes both the Bach and Einstein tensors and the cosmological terms. © 2017 IOP Publishing Ltd and Sissa Medialab srl.

Spin Dynamics and Establishing of Internal Quasi-Equilibrium in Dilute Paramagnetic Solids / Dzheparov,F.S.; // Zeitschrift fur Physikalische Chemie. - 2017. - 231. - с. 545-560

Annotation:

A brief review is given of the development and experimental verification of the two-temperature quasi-equilibrium concept as applied to EPR in dilute paramagnetic solids. Existing experimental data on spectral diffusion in a dipolar broadened EPR line and excitation transfer inside the electron dipolar reservoir are newly considered. The discussion is supplemented with theoretical arguments based on the concentration and cluster expansion techniques. Conditions and limitations of applicability of the two-temperature quasi-equilibrium model to electron spin systems with random distribution of paramagnetic centers are cleared up. © 2017 Walter de Gruyter GmbH, Berlin/Boston.

Calculation of the Astrophysical S -Factor S12 with the Lorentz Integral Transform / Efros,V.D.; // Few-Body Systems. - 2017. - 58. - с.

Annotation:

The LIT approach is tested for the calculation of astrophysical S-factors. As an example the S-factor of the reaction 2H (p, γ) 3He is considered. It is discussed that a sufficiently high density of LIT states at low energies is necessary for a precise determination of S-factors. In particular it is shown that the hyperspherical basis is not very well suited for such a calculation and that a different basis system is much more advantageous. A comparison of LIT results with calculations, where continuum wave functions are explicitly used, shows that the LIT approach leads to reliable results. It is also shown how an error estimate of the LIT inversion can be obtained. © 2016, Springer-Verlag Wien.

Determination of S-Factors with the LIT Method / Efros,V.D.; // Few-Body Systems. - 2017. - 58. - с.

Annotation:

The precise determination of astrophysical S-factors is essential for a detailed understanding of the nucleosynthesis in its various facets. It is discussed how the Lorentz integral transform (LIT) method can be applied for such a determination. The astrophysical S-factor for the proton–deuteron radiative capture is considered as test case. The importance of a specific many-body basis used for the LIT equation solution is pointed out. The excellent results of the test are discussed. © 2017, Springer-Verlag Wien.

Determination of the scalar polarizabilities of the proton using beam asymmetry Σ3 in Compton scattering / Lensky,V.; // European Physical Journal A. - 2017. - 53. - с.

Annotation:

The scalar dipole polarizabilities, αE 1 and βM 1, are fundamental properties related to the internal dynamics of the nucleon. The currently accepted values of the proton polarizabilities were determined by fitting to unpolarized proton Compton scattering cross section data. The measurement of the beam asymmetry Σ3 in a certain kinematical range provides an alternative approach to the extraction of the scalar polarizabilities. At the Mainz Microtron (MAMI) the beam asymmetry was measured for Compton scattering below pion photoproduction threshold for the first time. The results are compared with model calculations and the influence of the experimental data on the extraction of the scalar polarizabilities is determined. © 2017, SIF, Springer-Verlag Berlin Heidelberg.

Bottomonium-like states: Physics case for energy scan above the BB threshold at Belle-II / Mizuk,R.V.; // Modern Physics Letters A. - 2017. - . - с.

Annotation:

The Belle-II experiment is expected to collect large data samples at the (Formula presented.) and (Formula presented.) resonances to study primarily (Formula presented.) and (Formula presented.) mesons. We discuss what other data above the (Formula presented.) threshold are of interest. We propose to perform a high-statistics energy scan from the (Formula presented.) threshold up to the highest possible energy, and to collect data at the (Formula presented.) and at higher mass states if they are found in the scan. We emphasize the interest in increasing the maximal energy from 11.24 GeV to 11.5–12 GeV in the future. These data are needed for the investigation of bottomonium and bottomonium-like states. © 2017 World Scientific Publishing Company

Critical charge in gapped graphene: The role of screening of the interaction potential by σ-orbitals / Pavlovsky,O.; // International Journal of Modern Physics B. - 2017. - . - с.

Annotation:

Due to its unique structure, graphene provides a condensed-matter model of particle physics phenomena. One is the critical charge which is highly interested. The investigation of critical charge in gapped graphene is performed within single particle approach by means of Dirac equation integration. The screened Coulomb interaction between charged defect and graphene electron excitations is investigated. Two kinds of mass gap generation and various values of substrate dielectric permittivities are considered. It is shown that the critical charge phenomenon can be observed even with quite small charges for physically motivated parameters. © 2017 World Scientific Publishing Company

Exponential difference schemes for solving boundary-value problems for convection-diffusion type equations / Polyakov,S.V.; // Mathematical Models and Computer Simulations. - 2017. - 9. - с. 71-82

Annotation:

The paper considers the numerical solution of boundary-value problems for multidimensional convection-diffusion type equations (CDEs). Such equations are useful for various physical processes in solids, liquids and gases. A new approach to the spatial approximation for such equations is proposed. This approach is based on an integral transformation of second-order one-dimensional differential operators. A linear version of CDE was chosen for simplicity of the analysis. In this setting, exponential difference schemes were constructed, algorithms for their implementation were developed, a brief analysis of the stability and convergence was made. This approach was numerically tested for a two-dimensional problem of motion of metallic particles in water flow subject to a constant magnetic field. © 2017, Pleiades Publishing, Ltd.

Precursors of short gamma-ray bursts in the SPI-ACS/INTEGRAL experiment / Pozanenko,A.S.; // Astronomy Letters. - 2017. - 43. - с.

Annotation:

We have analyzed the light curves of 519 short gamma-ray bursts (GRBs) detected in the SPI-ACS/INTEGRAL experiment from December 2002 toMay 2014 to search for precursors (a possible activity of the GRB source before the beginning of themain episode). Both the light curves of 519 individual events and the averaged light curve of 372 brightest bursts have been analyzed. In several cases, we have found and thoroughly studied precursor candidates based on SPI-ACS/INTEGRAL, GBM/Fermi, and LAT/Fermi data. A statistical analysis of the averaged light curve for the entire sample of short bursts has revealed no regular precursor. Upper limits for the relative intensity of precursors have been estimated. We have compared our results with those of other authors; no convincing evidence for the existence of precursors of short GRBs has been found. We show that the fraction of short GRBs with precursors is less than 0.4% of all short bursts. © 2017, Pleiades Publishing, Inc.

Gate simulation of Compton Ar-Xe gamma-camera for radionuclide imaging in nuclear medicine / Dubov,L.Yu.; Belyaev,V.N.; Berdnikova,A.K.; Bolozdynia,A.I.; Akmalova,Yu.A.; Shtotsky,Yu.V.; // Journal of Physics: Conference Series. - 2017. - 784. - с.

Annotation:

Computer simulations of cylindrical Compton Ar-Xe gamma camera are described in the current report. Detection efficiency of cylindrical Ar-Xe Compton camera with internal diameter of 40 cm is estimated as1-3%that is 10-100 times higher than collimated Anger's camera. It is shown that cylindrical Compton camera can image Tc-99m radiotracer distribution with uniform spatial resolution of 20 mm through the whole field of view. © Published under licence by IOP Publishing Ltd.

Investigation of structure and heterogeneity of the plastic deformation in bimetal exposed to uniaxial tension / Galina,S.; // AIP Conference Proceedings. - 2017. - 1800. - с.

Annotation:

This paper presents features and heterogeneity of yielding at micro- and macro-scale levels of corrosion-resistant bimetal based on a compound of austenitic stainless steel (301 AISI) and low-carbon construction steel (A 283 Grade C) using the methods of scanning-electron, atomic force and optical microscopy. The staging of stress-strain curves was analyzed. © 2017 Author(s).

Software simulators for the evaluation of socio-personal competence for certification of qualifications of university graduates / Guseva,A.I.; Kireev,V.S.; Silenko,A.N.; Tikhomirov,G.V.; Sheina,E.A.; // AIP Conference Proceedings. - 2017. - 1797. - с.

Annotation:

This article discusses the issues associated with the use of software simulators for the evaluation of competences for certification of qualifications of employees of the nuclear industry. This study was conducted for the expert and methodical center of assessment and certification of qualifications of specialists in the nuclear industry, based on the National nuclear innovation consortium. The goal of this study is to build a model for assessing the socio-personal competence and its realization in the form of a software simulator. The study was conducted among a large number of senior students MEPhI - future managers, IT professionals, and nuclear physicists. As a result of the survey five classes of students have been allocated differently performing case studies, and for and for different areas of training recommendations on the use of various educational technologies have been made. © 2017, American Institute of Physics Inc. All rights reserved.

Superelasticity of Ti-Nb-Zr alloys and their medical application / Isaenkova,M.; Perlovich,Y.; Efimova,E.; Zhuk,D.; Krymskaya,O.; // Materials Science Forum. - 2017. - 879. - с. 2561-2566

Annotation:

In this paper investigation results of behavior of promising superelastic alloys of Ti-Nb-Zr system in blood-vessel are presented. The possibility of their use in manufacturing of medical stents is examined. Based on analytical review of present scientific papers, four different alloys of Ti-Nb-Zr system are taken in consideration. A finite element modelling of stent behavior during delivery and opening stages is considered. These processes are done for two typical stent geometries and four alloys possessing different mechanical properties. Finite modelling results are analyzed to show the distribution of internal stresses, mechanical aspects of stent installation and effectiveness of various configurations to widen the narrowed vessel. Modeling has allowed to formulate recommendations for optimal mechanical characteristics of the superelastic alloy used for the manufacture of medical stents. © 2017 Trans Tech Publications, Switzerland.

On the synchro-curvature radiation / Kelner,S.R.; Aharonian,F.A.; // AIP Conference Proceedings. - 2017. - 1792. - с.

Annotation:

It is generally believed that the radiation of relativistic particles in a curved magnetic field proceeds in either the synchrotron or the curvature radiation modes. We study an intermediate, the so-called synchro-curvature regime. Using the Hamiltonian formalism, we find the trajectory of relativistic particle in the curved magnetic field that has the form of a helix wound around the drift trajectory. We show that the transition to the limit of the synchrotron and curvature radiation regimes is determined by relation between curvatures of the drift trajectory and gyration motion around it. When both are approximately equal, the curvature of the trajectory start to noticeably oscillate with the frequency of particle gyration leading to the synchro-curvature radiation with averaged spectrum different from synchrotron or curvature one. The performed numerical calculations with energy losses and different initial pitch angles confirm the principal conclusions based on the simplified analytical treatment. © 2017 Author(s).

The "pHOENIX" Space Experiment: Study of Space Radiation Impact on Cells Genetic Apparatus on Board the International Space Station / Kushin,V.V.; Inozemtsev,K.O.; // Journal of Physics: Conference Series. - 2017. - 784. - с.

Annotation:

The preliminary results of the 1st session of Russian "PHOENIX" long-term space experiment are presented. The survival of dried human lymphocytes and mouse bone marrow cells in 199 days space flight is studied. The degree of DNA fragmentation is analysed for samples flown in different ISS compartments. It is shown that biological data correlates with the results of space radiation dose measurements. © Published under licence by IOP Publishing Ltd.

Production of Nd-Fe Foundry Alloy by Electrolysis in Molten Salts / Makaseev,Y.; Buinovskiy,A.; Zhitkov,S.; Kartashov,E.; Sofronov,V.; // MATEC Web of Conferences. - 2017. - 96. - с.

Annotation:

Nd-Fe-B-based permanent magnets have the highest magnetic characteristics. To improve their quality, one generally applies the technique of solid-phase alloying by materials with high content of neodymium, dysprosium, terbium, i.e. rare-earth metal (REM)-Fe(Co) foundry alloys. The paper presents the results of the study of the manufacturing process of Nd-Fe foundry alloys, with composition being close to eutectic, by electrolysis of neodymium oxides and fluorides from chloride and fluoride melts. It is shown that in the oxide electrolysis a sufficiently high current efficiency (over 98 %) is obtained. This is a promising method of obtaining of rare earth-containing materials. © The Authors, published by EDP Sciences, 2017.

Science, education and industry information resources complementarity as a basis for design of knowledge management systems / Maksimov,N.V.; Tikhomirov,G.V.; Golitsina,O.L.; // AIP Conference Proceedings. - 2017. - 1797. - с.

Annotation:

The main problems and circumstances that influence the processes of creating effective knowledge management systems were described. These problems particularly include high species diversity of instruments for knowledge representation, lack of adequate lingware, including formal representation of semantic relationships. For semantic data descriptions development a conceptual model of the subject area and a conceptual-lexical system should be designed on proposals of ISO-15926 standard. It is proposed to conduct an information integration of educational and production processes on the basis of information systems technologies. Integrated knowledge management system information environment combines both traditional information resources and specific information resources of subject domain including task context and implicit/tacit knowledge. © 2017, American Institute of Physics Inc. All rights reserved.

Assessment of organochlorine hydrocarbons transformation in contaminated agricultural products and foodstuffs under gamma-radiation / Mel'Nikova,T.V.; Polyakova,L.P.; Oudalova,A.A.; // Journal of Physics: Conference Series. - 2017. - 784. - с.

Annotation:

The problem of an estimation of organochlorinated pollutants transformation (particularly organochlorinated pesticides (OCP) and polychlorinated biphenyls (PCB)) under gamma-irradiation has become important in connection with radiation technologies application in the food industry. According to earlier researches, small doses of OCP lead to serious damages of an organism, comparable with damages from high doses. Among radiolysis products of OCP in model solutions various substances on a structure have been found out. Though of trace concentration of each of them, in sum with the initial pesticides residue they make up significant of mass contamination (as shown earlier up to 90% from initial OCP). In this work fish samples (bream) containing OCPs (15.20 ng/g of hexachlorocyclohexane isomers and 87.10 ng/g of DDT and its metabolites), as well as PCB (18.51 ng/g) were studied. The minced fish was irradiated at dose of 10 kGy with dose rate of 1.35 Gy/sec. Then, by methods of gas-liquid chromatography (GLC) and gas chromatography-mass spectrometry (GC-MS), it was found that the OCPs degradation varied from 3 up to 61% and the PCB degradation - 24-52%. Significant complication of chemical composition was shown comparing to the primary biological sample contamination. As a result of fish irradiation, secondary pollution appeared that included residues of primary organochlorine hydrocarbons and their radiation-induced metabolites. Among the investigated OCPs the most stable proved to be alfa-hexachlorocyclohexane (alfa-HCH), the least stable - DDT which corresponds to the previous findings about the radiation stability of OCPs in model solutions. Mass spectra of the irradiated samples of minced bream showed the presence of radiation metabolites of OCPs, that had also been found at irradiation of model solutions of 2,2-di(4-chlorophenyl)-1-chlorethylene (DDMU), DDD and 1a, 2e, 3e, 4e, 5e-pentahlorcyclohexane. There was revealed a decomposition product formed during the deep destruction of chlorinated xenobiotics molecules - 1,1,2-trichloro-4-methyl-1-pentene (C6H9Cl3); this substance was absent in the original fish samples. In the samples of irradiated fish there was not defined any OCP oxidation products or any intermediates that may be due to the conditions of sample preparation. To estimate toxicity of the secondary pollution, integral bioassays methods are proposed to apply. Introduction. © Published under licence by IOP Publishing Ltd.

Biotesting of radioactively contaminated forest soils using barley-based bioassay / Mel'Nikova,T.V.; Polyakova,L.P.; Oudalova,A.A.; // Journal of Physics: Conference Series. - 2017. - 784. - с.

Annotation:

Findings from radioactivity and phytotoxicity study are presented for soils from nine study-sites of the Klintsovsky Forestry located in the Bryansk region that were radioactively contaminated after the Chernobyl accident. According to the bioassay based on barley as test-species, stimulating effect of the soils analyzed is revealed for biological indexes of the length of barley roots and sprouts. From data on 137Cs specific activities in soils and plant biomass, the migration potential of radionuclide in the «soil-plant» system is assessed as a transfer factor. With correlation analysis, an impact of 137Cs in soil on the biological characteristics of barley is estimated. © Published under licence by IOP Publishing Ltd.

Health risk assessment of potable water containing small amount of tritium oxide / Momot,O.A.; Synzynys,B.I.; Oudalova,A.A.; // Journal of Physics: Conference Series. - 2017. - 784. - с.

Annotation:

The problem of groundwater pollution with tritium in a vicinity of radiation-dangerous facilities in Obninsk is considered. The information on the specific activity of tritium in Obninsk water sources is provided. The formula for the calculation of the β-radiation absorbed dose from tritium ingestion is proposed, reflecting the biological behavior of tritium in a human body. To establish the extent of tritium effects on human, the health risk is assessed. It is shown that if the specific activity of tritium in drinking water amounts to 10 Bq/l, the risk of stochastic effects of radiation will not exceed the limit of the individual lifetime risk. © Published under licence by IOP Publishing Ltd.

Allium-test as a tool for toxicity testing of environmental radioactive-chemical mixtures / Oudalova,A.A.; Pyatkova,S.V.; // Journal of Physics: Conference Series. - 2017. - 784. - с.

Annotation:

Bioassay-based approaches have been propagated to assess toxicity of unknown mixtures of environmental contaminants, but it was rarely applied in cases of chemicals with radionuclides combinations. Two Allium-test studies were performed to assess environmental impact from potential sources of combined radioactive-chemical pollution. Study sites were located at nuclear waste storage facilities in European and in Far-Eastern parts of Russia. As environmental media under impact, waters from monitor wells and nearby water bodies were tested. Concentrations of some chemicals and radionuclides in the samples collected enhanced the permitted limits. Cytogenetic and cytotoxic effects were used as biological endpoints, namely, frequency and spectrum of chromosome aberrations and mitotic abnormalities in anatelophase cells as well as mitotic activity in Allium root tips. Sample points were revealed where waters have an enhanced mutagenic potential. The findings obtained could be used to optimize monitoring system and advance decision making on management and rehabilitation of industrial sites. The Allium-test could be recommended and applied as an effective tool for toxicity testing in case of combined contamination of environmental compartments with radionuclides and chemical compounds. © Published under licence by IOP Publishing Ltd.

The effect of high-doze neutron irradiation on texture and substructure condition of cladding tubes from Zr-based alloys / Perlovich,Y.; Isaenkova,M.; Krymskaya,O.; Fesenko,V.; // Materials Science Forum. - 2017. - 879. - с. 1483-1488

Annotation:

Texture and substructure changes in cladding tubes from Zr-based alloys under neutron irradiation in the atomic reactor during 6 years were investigated by use of X-ray methods. For this aim in the “hot” laboratory the automated X-ray diffractometer was set and the technique to handle with irradiated samples was elaborated. The residual radiation activity of samples correlates with integral texture Kearns parameters of tube, so that the texture weakens as the doze of neutron irradiation grows. Because of the initial substructure inhomogeneity of cladding tubes its changes under neutron irradiation are also inhomogeneous: relatively perfect grains of texture maxima become more distorted, whereas initially distorted grains of texture minima becomes more perfect. © 2017 Trans Tech Publications, Switzerland.

Effect of layer-by-layer texture inhomogeneity on the stress corrosion of gas steel tubes / Perlovich,Y.; Krymskaya,O.; Isaenkova,M.; Morozov,N.; // Materials Science Forum. - 2017. - 879. - с. 1025-1030

Annotation:

Based on the data of X-ray texture and structure analysis of the material of main gas pipelines it was shown that the layerwise inhomogeneity of tubes is formed during their manufacturing. The layerwise texture inhomogeneity of steel tubes, obtained by hot rolling at the air, differs depending on variation of technological parameters of their processing in inner and outer layers, i.e. the temperature and deformation gradients, penetration of interstitial impurities into the surface layer from surrounding atmosphere etc. The thickness of the surface layer with modified texture parameters depends on the temperature of rolling and its regime. Under exploitation when stress-corrosion cracks grows and reach the layer with a modified texture, their opening is slowing down or stops because of the high mutual misorientation of grains of different layers and the necessity of changing the plane of moving cracks, what requires additional tensile stresses. Layered textures of different gas tubes were compared. It was shown that character and degree of arising inhomogeneity correlates with the tubes resistance to stress-corrosion cracking. © 2017 Trans Tech Publications, Switzerland.

2016
A comparison of learning abilities of spiking networks with different spike timing-dependent plasticity forms / Serenko,A. [etc.] / Journal of Physics: Conference Series. - 2016.

Annotation:

A study of possibility to model the learning process on base of different forms of timing-dependent plasticity (STDP) was performed. It is shown that the learning ability depends on the choice of spike pairing scheme and the type of input signal used for learning. The comparison of performance of several STDP rules along with several neuron models (leaky integrate-and-fire, static, Izhikevich and Hodgkin-Huxley) was carried out using the NEST simulator. The combinations of input signal and STDP spike pairing scheme, which demonstrate the best learning abilities, were extracted.

A first walk on the DarkSide / Davini,S. / Nuclear and Particle Physics Proceedings. - 2016.

Annotation:

DarkSide-50 (DS-50) at Gran Sasso underground laboratory (LNGS), Italy, is a direct dark matter search experiment based on a TPC with liquid argon. DS-50 has completed its first dark matter run using atmospheric argon as target. The DS-50 detector performances and the results of the first physics run are reviewed in this proceeding. © 2015 Elsevier B.V.

A new method to distinguish hadronically decaying boosted Z bosons from W bosons using the ATLAS detector / AtlasCollaboration / European Physical Journal C. - 2016.

Annotation:

The distribution of particles inside hadronic jets produced in the decay of boosted W and Z bosons can be used to discriminate such jets from the continuum background. Given that a jet has been identified as likely resulting from the hadronic decay of a boosted W or Z boson, this paper presents a technique for further differentiating Z bosons from W bosons. The variables used are jet mass, jet charge, and a b-tagging discriminant. A likelihood tagger is constructed from these variables and tested in the simulation of Wsup′/sup→ WZ for bosons in the transverse momentum range 200 GeV < pT< 400 GeV in s= 8 TeV pp collisions with the ATLAS detector at the LHC. For Z-boson tagging efficiencies of ϵZ= 90 , 50, and 10 % , one can achieve Wsup+/sup-boson tagging rejection factors (1 / ϵW+) of 1.7, 8.3 and 1000, respectively. It is not possible to measure these efficiencies in the data due to the lack of a pure sample of high pT, hadronically decaying Z bosons. However, the modelling of the tagger inputs for boosted W bosons is studied in data using a tt¯ -enriched sample of events in 20.3 fbsup- 1/sup of data at s= 8 TeV. The inputs are well modelled within uncertainties, which builds confidence in the expected tagger performance. © 2016, CERN for the benefit of the ATLAS collaboration.

A practical parametrisation of line shapes of near-threshold resonances / Hanhart,C / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

A practical parametrisation for the line shapes of near threshold resonance(s) is derived in the framework of a coupled-channel model which includes an arbitrary number of elastic and inelastic channels as well as a bare pole term. The parameters have a direct relation to phenomenology and can be employed to study the nature of the near-threshold states. The resulting analytical parametrisation is therefore ideally suited to investigate the full information content provided by the measurements and to establish a link between the experimental data and their theoretical interpretation.

A search for pair production of new light bosons decaying into muons / Khachatryan,V. / Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 2016.

Annotation:

A search for the pair production of new light bosons, each decaying into a pair of muons, is performed with the CMS experiment at the LHC, using a dataset corresponding to an integrated luminosity of 20.7 fbsup-1/sup collected in proton-proton collisions at center-of-mass energy of √s=8 TeV. No excess is observed in the data relative to standard model background expectation and a model independent upper limit on the product of the cross section, branching fraction, and acceptance is derived. The results are compared with two benchmark models, the first one in the context of the next-to-minimal supersymmetric standard model, and the second one in scenarios containing a hidden sector, including those predicting a nonnegligible light boson lifetime. © 2015 CERN for the benefit of the CMS Collaboration.

A search for prompt lepton-jets in pp collisions at (Formula presented.) TeV with the ATLAS detector / TheATLAScollaboration / Journal of High Energy Physics. - 2016.

Annotation:

Abstract: A search is presented for a new, light boson with a mass of about 1 GeV and decaying promptly to jets of collimated electrons and/or muons (lepton-jets). The analysis is performed with 20.3 fbsup−1/sup of data collected by the ATLAS detector at the Large Hadron Collider in proton-proton collisions at a centre-of-mass energy of 8 TeV. Events are required to contain at least two lepton-jets. This study finds no statistically significant deviation from predictions of the Standard Model and places 95% confidence-level upper limits on the contribution of new phenomena beyond the SM, incuding SUSY-portal and Higgs-portal models, on the number of events with lepton-jets.[Figure not available: see fulltext.] © 2016, The Author(s).

Accumulation and annealing of radiation defects and the hydrogen effect thereon in an austenitic steel 16Cr15Ni3Mo1Ti upon low-temperature neutron and electron irradiation / Arbuzov,V.L. / Physics of Metals and Metallography. - 2016.

Annotation:

The effect of hydrogen, accumulation and annealing of radiation defects on the physicomechanical properties of an austenitic Kh16N15M3T1 steel (16Cr15Ni3Mo1Ti) has been investigated upon low-temperature (77 K) neutron and electron irradiations. It has been shown that, when its concentration is about 300 at ppm, hydrogen reduces plasticity by 25%. The presence of helium (2.0–2.5 at ppm) introduced by the tritium-trick method exerts an effect on the yield strength and hardly affects embrittlement. Upon both electron and neutron irradiation, there is a linear relation between the increment of the yield strength and the square root of the increment of the residual electrical resistivity (the concentration of radiation defects). The annealing of vacancies occurs in the neighborhood of 300 K (energy for vacancy migration is 1.0–1.0 eV). Vacancy clusters dissociate near 480 K (energy for dissociation is 1.4–1.5 eV). © 2016, Pleiades Publishing, Ltd.

Duration distributions for gamma-ray bursts registered in various experiments since VENERA11/KONUS up to Fermi/GBM / Arkhangelskaja,IV // INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

Gamma-ray bursts duration distributions properties for events registered by experiments CGRO/BATSE, VENERA11/KONUS, VENERA12/KONUS, Swift/BAT, GRANAT/PHEBUS, Suzaku/WAM, RHESSI and Fermi/GBM are considered. GRBs observed since 1967 and now several thousands of events were listed in more than 30 catalogues. Gamma-ray bursts duration distribution was the first analysed using data of BATSE instrument onboard the CGRO. The GRBs duration distribution analysis had shown the existence of two bursts classes: long and short separated by t(90) = 2 s. But results of similar distributions for bursts observed by other detectors have shown shifting of boundary between short and long events from value of 2 s. For example, Swift/BAT GRBs subset analysis gives the value of similar to 1 s for this separator point. Moreover, t(90) has dependence from instrument registered this burst -it is function of detector sensitivity threshold and operation energy band. For instance, the duration of GRB060418 burst t(90) is similar to 52 s according to Swift/BAT data and only 36 s according to RHESSI data. Therefore, the type of GGB (whether it short or long) should be defined only taking into account distinctive features of instrument detected this event. Also attributes of third intermediate GRBs subgroup appearance in events subsets for various detectors are discussed. Firstly this subgroup was found some years ago in BATSE GRB duration and duration-hardness distributions.

The background model in the energy range from 0.1 MeV up to several MeV for low altitude and high inclination satellites / Arkhangelskaja,IV, Arkhangelskiy,AI // INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

The gamma-ray background physical origin for low altitude orbits defined by: diffuse cosmic gamma-emission, atmospheric gamma-rays, gamma-emission formed in interactions of charged particles (both prompt and activation) and transient events such as electrons precipitations and solar flares. The background conditions in the energy range from 0.1 MeV up to several MeV for low altitude orbits differ due to frequency of Earth Radiation Belts - ERBs (included South Atlantic Anomaly - SAA) passes and cosmic rays rigidity. The detectors and satellite constructive elements are activated by trapped in ERBs and moving along magnetic lines charged particles. In this case we propose simplified polynomial model separately for polar and equatorial orbits parts: background count rate temporal profile approximation by 4-5 order polynomials in equatorial regions, and linear approximations, parabolas or constants in polar caps. The polynomials' coefficients supposed to be similar for identical spectral channels for each analyzed equatorial part taken into account normalization coefficients defined due to Kp-indexes study within period corresponding to calibration coefficients being approximately constants. The described model was successfully applied for the solar flares hard X-ray and gamma-ray emission characteristic studies by AVS-F apparatus data onboard CORONAS-F satellite.

Assessment of segregation kinetics in water-moderated reactors pressure vessel steels under long-term operation / Gurovich,B.A. / Journal of Nuclear Materials. - 2016.

Annotation:

In reactor pressure vessel (RPV) bcc-lattice steels temper embrittlement is developed under the influence of both operating temperature of ∼300 °C and neutron irradiation. Segregation processes in the grain boundaries (GB) begin to play a special role in the assessment of the safe operation of the RPV in case of its lifetime extension up to 60 years or more. The most reliable information on the RPV material condition can be obtained by investigating the surveillance specimens (SS) that are exposed to operational factors simultaneously with the RPV itself. In this paper the GB composition in the specimens with different thermal exposure time at the RPV operating temperature as well as irradiated by fast neutrons (E ≥ 0.5 MeV) to different fluences (20-71)·10sup22/sup msup-2/sup was studied by means of Auger electron spectroscopy (AES) including both impurity and main alloying elements content. The data obtained allowed to trace the trend of the operating temperature and radiation-stimulated diffusion influence on the overall segregants level in GB. The revealed differences in the concentration levels of GB segregants in different steels, are due to the different chemical composition of the steels and also due to different grain boundary segregation levels in initial (unexposed) state. The data were used to estimate the RPV steels working capacity for 60 years. The estimation was carried out using both the well-known Langmuir-McLean model and the one specially developed for RPV steels, which takes into account the structure and phase composition of VVER-1000 RPV steels, as well as the long-term influence of operational factors. © 2016 Elsevier B.V.

Athermal laser annealing of cold-worked aluminum / Kazilin,E.E. / Inorganic Materials: Applied Research. - 2016.

Annotation:

The influence of pulsed laser irradiation on mechanical properties of annealed and cold-worked pure aluminum is studied. Mechanical tests are performed by means of a miniaturized disk bend test technique using specimens with the diameter of 3 mm. It is established that laser irradiation does not influence the mechanical properties of annealed aluminum but leads to softening of cold-worked material. After 100 laser pulses, nearly complete recovery of aluminum strength occurs to the value characteristic of the annealed state. The plasticity of cold-worked aluminum is lower than that of annealed material and does not vary upon laser irradiation. Thermal and shock-wave mechanisms of laser impact are estimated, and it follows that, under the given parameters of irradiation, the main contribution to the variation of properties is that of shock-wave mechanism related to generation and propagation of acoustic waves which stimulate athermal annealing and recovery of dislocation structure. © 2016, Pleiades Publishing, Ltd.

Atmospheric effects in the intensity of muon bundles and geometrical mechanism of their formation / Kokoulin,RP / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

Temporal changes in the intensity of muon bundles produced as a result of interactions of primary cosmic ray particles with energies of the order of 1015 eV and detected at the ground level are analyzed. Seasonal variations, barometric and temperature effects, and correlations with the altitudes of various levels of residual pressure are considered. It is shown that muon bundle intensity variations are well explained in frame of a simple mechanism related with changes of the muon lateral distribution function at the observation level caused by geometrical changes of the effective altitude of the formation of the bundles.

Estimation of atmospheric neutrinos background in Borexino / Atroshchenko,VS, Litvinovich,EA // INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

Atmospheric neutrinos are produced in interactions of cosmic rays with atomic nuclei in the Earth's atmosphere. Although their flux is too low for studying in Borexino, atmospheric neutrinos act as a background for other processes. This paper presents the theoretical expected yield of atmospheric neutrinos in Borexino for three neutrino detection reactions: vp-ES, ve-ES and inverse beta-decay, as well as the status of Monte-Carlo simulation for v(12)C interaction channels. Calculations were performed based on the only currently known detailed model of atmospheric neutrinos flux at very low energies.

Azimuthal anisotropy of charged jet production in sNN=2.76 TeV Pb-Pb collisions / Adam,J. / Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 2016.

Annotation:

We present measurements of the azimuthal dependence of charged jet production in central and semi-central sNN=2.76 TeV Pb-Pb collisions with respect to the second harmonic event plane, quantified as v2ch jet. Jet finding is performed employing the anti-kT algorithm with a resolution parameter R=0.2 using charged tracks from the ALICE tracking system. The contribution of the azimuthal anisotropy of the underlying event is taken into account event-by-event. The remaining (statistical) region-to-region fluctuations are removed on an ensemble basis by unfolding the jet spectra for different event plane orientations independently. Significant non-zero v2ch jet is observed in semi-central collisions (30-50% centrality) for 20pTch jet90 GeV/c. The azimuthal dependence of the charged jet production is similar to the dependence observed for jets comprising both charged and neutral fragments, and compatible with measurements of the v2 of single charged particles at high pT. Good agreement between the data and predictions from JEWEL, an event generator simulating parton shower evolution in the presence of a dense QCD medium, is found in semi-central collisions. © 2015 CERN for the benefit of the ALICE Collaboration.

Modeling of the charge-state separation at ITEP experimental facility for material science based on a Bernas ion source / Barminova,H.Y., Saratovskyh,M.S. // Review of Scientific Instruments. - 2016.

Annotation:

The experiment automation system is supposed to be developed for experimental facility for material science at ITEP, based on a Bernas ion source. The program CAMFT is assumed to be involved into the program of the experiment automation. CAMFT is developed to simulate the intense charged particle bunch motion in the external magnetic fields with arbitrary geometry by means of the accurate solution of the particle motion equation. Program allows the consideration of the bunch intensity up to 10sup10/sup ppb. Preliminary calculations are performed at ITEP supercomputer. The results of the simulation of the beam pre-acceleration and following turn in magnetic field are presented for different initial conditions. © 2015 AIP Publishing LLC.

Be-8 and B-9 nuclei in dissociation of relativistic B-10 and C-11 nuclei / Bradnova,V / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

Progress in the study of nuclear clustering in the relativistic B-10 and C-11 nuclei dissociation in nuclear track emulsion is presented. The contribution of the unbound Be-8 and B-9 nuclei to their structure is determined on the basis of measurements of the emission angles of relativistic He and H fragments.

Beam Energy Dependence of the Third Harmonic of Azimuthal Correlations in Au+Au Collisions at RHIC / Adamczyk,L. / Physical Review Letters. - 2016.

Annotation:

©, where φ1-φ2 is the angular difference in azimuth, is studied as a function of the pseudorapidity difference between particle pairs Δη=η1-η2. Nonzero v322 is directly related to the previously observed large-Δη narrow-Δφ ridge correlations and has been shown in models to be sensitive to the existence of a low viscosity quark gluon plasma phase. For sufficiently central collisions, v322 persist down to an energy of 7.7 GeV, suggesting that quark gluon plasma may be created even in these low energy collisions. In peripheral collisions at these low energies, however, v322 is consistent with zero. When scaled by the pseudorapidity density of charged-particle multiplicity per participating nucleon pair, v322 for central collisions shows a minimum near sNN=20 GeV.

Beam-induced and cosmic-ray backgrounds observed in the ATLAS detector during the LHC 2012 proton-proton running period / Aad,G / JOURNAL OF INSTRUMENTATION. - 2016.

Annotation:

This paper discusses various observations on beam-induced and cosmic-ray backgrounds in the ATLAS detector during the LHC 2012 proton-proton run. Building on published results based on 2011 data, the correlations between background and residual pressure of the beam vacuum are revisited. Ghost charge evolution over 2012 and its role for backgrounds are evaluated. New methods to monitor ghost charge with beam-gas rates are presented and observations of LHC abort gap population by ghost charge are discussed in detail. Fake jets from colliding bunches and from ghost charge are analysed with improved methods, showing that ghost charge in individual radio-frequency buckets of the LHC can be resolved. Some results of two short periods of dedicated cosmic-ray background data-taking are shown; in particular cosmic-ray muon induced fake jet rates are compared to Monte Carlo simulations and to the fake jet rates from beam background. A thorough analysis of a particular LHC fill, where abnormally high background was observed, is presented. Correlations between backgrounds and beam intensity losses in special fills with very high beta* are studied.

On the temperature evolution of multicomponent dark matter with Coulomb-like interaction / Belotsky,KM, Esipova,EA, Kirillov,AA // INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

We consider model of multicomponent dark matter consisting of WIMP- and SIMP-components, possessing Coulomb-like interaction. The latter, in its term, implies an existence of thermal background of the interaction carriers. We evaluate the temperature evolution of different components for early epoch. It is shown that it can be very different depending on model parameters.

Spherically symmetric conformal gravity and ''gravitational bubbles'' / Berezin,V.A., Eroshenko,Y.N., Dokuchaev,V.I. // Journal of Cosmology and Astroparticle Physics. - 2016.

Annotation:

The general structure of the spherically symmetric solutions in the Weyl conformal gravity is described. The corresponding Bach equations are derived for the special type of metrics, which can be considered as the representative of the general class. The complete set of the pure vacuum solutions is found. It consists of two classes. The first one contains the solutions with constant two-dimensional curvature scalar of our specific metrics, and the representatives are the famous Robertson-Walker metrics. One of them we called the ''gravitational bubbles'', which is compact and with zero Weyl tensor. Thus, we obtained the pure vacuum curved space-times (without any material sources, including the cosmological constant) what is absolutely impossible in General Relativity. Such a phenomenon makes it easier to create the universe from ''nothing''. The second class consists of the solutions with varying curvature scalar. We found its representative as the one-parameter family. It appears that it can be conformally covered by the thee-parameter Mannheim-Kazanas solution. We also investigated the general structure of the energy-momentum tensor in the spherical conformal gravity and constructed the vectorial equation that reveals clearly some features of non-vacuum solutions. Two of them are explicitly written, namely, the metrics. © 2016 IOP Publishing Ltd and Sissa Medialab srl.

Cosmic ray physics with TeV muons in large volume detectors / Berghaus,Patrick // INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

Large volume detectors such as IceCube, designed for the detection of astrophysical neutrinos register cosmic ray-induced atmospheric muon bundles at a rate of several thousand events per second. Due to the large amount of surrounding material, the effective energy threshold for muons reaching the detector typically lies at approximately one TeV. Through careful evaluation of event profiles it is possible to address cosmic ray and particle physics issues in an unprecedented energy region. Results from the analysis of one year of IceCube data are presented and their implications discussed.

Blister formation on 13Cr2MoNbVB ferritic-martensitic steel exposed to hydrogen plasma / Nikitin,A.V. / Journal of Nuclear Materials. - 2016.

Annotation:

The influence of pre-irradiation specimen deformation level on surface blister formation and sub-surface cracking of dual-phase 13Cr2MoNbVB ferritic-martensitic steel was studied using glow discharge hydrogen plasma with ion energy of 1 keV to fluences of 2 × 1025 H/m2. Protium was used for most studies, but deuterium was used for measuring the depth dependence of hydrogen diffusion. Formation of blisters was observed in the temperature range 230-340 K. It was found that pre-irradiation deformation caused changes in the threshold fluences of blister formation and also in blister size distribution. Subsurface cracks located on grain boundaries far beyond the implantation zone were formed concurrently with blisters, arising from hydrogen diffusion and trapping at defects. It was observed that cracks as long as 1 mm in length were formed in 95% deformed steel at depths up to 500 μm from surface. © 2016 Elsevier B.V. All rights reserved.

Calculation of Design-Basis Accidents Loss of Coolant Circulation for the IRT MIFI Reactor / Shchurovskaya,M.V. / Atomic Energy. - 2016.

Annotation:

The results of calculations of emergency situations for the IRT MIFI [Moscow Engineering Physics Institute] reactor with high-enrichment uranium fuel and with conversion to IRT-3M fuel assemblies with fuel cores based on the alloy U–9%Mo in an aluminum matrix with 19.7% enrichment are presented. The transient processes due to disruption of coolant circulation during the execution of safety functions are examined. The PARET 7.5 software is used to calculate the transient processes. Special attention is focused on taking account of emergency protection engagement algorithms and the characteristic features of the devices monitoring the thermohydraulic parameters of the reactor in setting the initial data for the calculation of transient processes. © 2016 Springer Science+Business Media New York.

Carbides in Co–Re–Cr-based high-temperature alloys / Wanderka,N. / Journal of Materials Science. - 2016.

Annotation:

Co–Re-base alloys with very high melting point are being developed to supplement Ni-superalloys in future gas turbines in which much higher gas entry temperatures are expected. The microstructure of Co–17Re–23Cr–2.6C and Co–17Re–23Cr–1.2Ta–2.6C alloys has been investigated by scanning and transmission electron microscopy. These alloys are mainly strengthened by carbides of Cr and/or Ta, but it is not trivial to accurately quantify the composition of the carbides. The compositions of the various carbides in Co–Re–base alloys were quantified with near-atomic resolution using atom probe tomography. The Cr as well as Ta carbides exists in the alloys with different morphologies, ranging from extremely fine (nm scale) to large (μm scale) sizes. The composition and the crystal structure of the investigated phases were measured and reported. It is shown that both types of carbides are stable up to 1000 °C but the Ta carbides are more stable than the Cr carbides at 1200 °C after long-time ageing. They are also effective as strengthening precipitates. © 2016, Springer Science+Business Media New York.

Centrality and Transverse Momentum Dependence of Elliptic Flow of Multistrange Hadrons and φ Meson in Au+Au Collisions at sNN =200 GeV / Adamczyk,L. / Physical Review Letters. - 2016.

Annotation:

We present high precision measurements of elliptic flow near midrapidity (|y|<1.0) for multistrange hadrons and φ meson as a function of centrality and transverse momentum in Au+Au collisions at center of mass energy sNN=200 GeV. We observe that the transverse momentum dependence of φ and Ω v2 is similar to that of π and p, respectively, which may indicate that the heavier strange quark flows as strongly as the lighter up and down quarks. This observation constitutes a clear piece of evidence for the development of partonic collectivity in heavy-ion collisions at the top RHIC energy. Number of constituent quark scaling is found to hold within statistical uncertainty for both 0%-30% and 30%-80% collision centrality. There is an indication of the breakdown of previously observed mass ordering between φ and proton v2 at low transverse momentum in the 0%-30% centrality range, possibly indicating late hadronic interactions affecting the proton v2. © 2016 American Physical Society.

Centrality dependence of charged jet production in p–Pb collisions at √sNN = 5.02 TeV / AliceCollaboration,CERN / European Physical Journal C. - 2016.

Annotation:

Measurements of charged jet production as a function of centrality are presented for p–Pb collisions recorded at √sNN = 5.02 TeV with the ALICE detector. Centrality classes are determined via the energy deposit in neutron calorimeters at zero degree, close to the beam direction, to minimise dynamical biases of the selection. The corresponding number of participants or binary nucleon–nucleon collisions is determined based on the particle production in the Pb-going rapidity region. Jets have been reconstructed in the central rapidity region from charged particles with the anti-kT algorithm for resolution parameters R= 0.2 and R= 0.4 in the transverse momentum range 20 to 120 GeV/c. The reconstructed jet momentum and yields have been corrected for detector effects and underlying-event background. In the five centrality bins considered, the charged jet production in p–Pb collisions is consistent with the production expected from binary scaling from pp collisions. The ratio of jet yields reconstructed with the two different resolution parameters is also independent of the centrality selection, demonstrating the absence of major modifications of the radial jet structure in the reported centrality classes. © 2016, CERN for the benefit of the ALICE collaboration.

Centrality dependence of identified particle elliptic flow in relativistic heavy ion collisions at sNN =7.7-62.4 GeV / Adamczyk,L. / Physical Review C - Nuclear Physics. - 2016.

Annotation:

Elliptic flow (v2) values for identified particles at midrapidity in Au + Au collisions measured by the STAR experiment in the Beam Energy Scan at the Relativistic Heavy Ion Collider at sNN=7.7-62.4 GeV are presented for three centrality classes. The centrality dependence and the data at sNN=14.5 GeV are new. Except at the lowest beam energies, we observe a similar relative v2 baryon-meson splitting for all centrality classes which is in agreement within 15% with the number-of-constituent quark scaling. The larger v2 for most particles relative to antiparticles, already observed for minimum bias collisions, shows a clear centrality dependence, with the largest difference for the most central collisions. Also, the results are compared with a multiphase transport (AMPT) model and fit with a blast wave model. © 2016 American Physical Society.

Centrality dependence of pion freeze-out radii in Pb-Pb collisions at root s(NN)=2.76 TeV / Adam,J / PHYSICAL REVIEW C. - 2016.

Annotation:

We report on the measurement of freeze-out radii for pairs of identical-charge pions measured in Pb-Pb collisions at root s(NN) = 2.76 TeV as a function of collision centrality and the average transverse momentum of the pair k(T). Three-dimensional sizes of the system (femtoscopic radii), as well as direction-averaged one-dimensional radii are extracted. The radii decrease with k(T), following a power-law behavior. This is qualitatively consistent with expectations from a collectively expanding system, produced in hydrodynamic calculations. The radii also scale linearly with dN(ch)/d eta (1/3). This behavior is compared to world data on femtoscopic radii in heavy-ion collisions. While the dependence is qualitatively similar to results at smaller root s(NN), a decrease in the ratio R-out/R-side is seen, which is in qualitative agreement with a specific prediction from hydrodynamic models: a change from inside-out to outside-in freeze-out configuration. The results provide further evidence for the production of a collective, strongly coupled system in heavy-ion collisions at the CERN Large Hadron Collider.

Centrality Dependence of the Charged-Particle Multiplicity Density at Midrapidity in Pb-Pb Collisions at sNN =5.02 TeV / Adam,J. / Physical Review Letters. - 2016.

Annotation:

The pseudorapidity density of charged particles, dNch/dη, at midrapidity in Pb-Pb collisions has been measured at a center-of-mass energy per nucleon pair of sNN=5.02 TeV. For the 5% most central collisions, we measure a value of 1943±54. The rise in dNch/dη as a function of sNN is steeper than that observed in proton-proton collisions and follows the trend established by measurements at lower energy. The increase of dNch/dη as a function of the average number of participant nucleons, Npart, calculated in a Glauber model, is compared with the previous measurement at sNN=2.76 TeV. A constant factor of about 1.2 describes the increase in dNch/dη from sNN=2.76 to 5.02 TeV for all centrality classes, within the measured range of 0%-80% centrality. The results are also compared to models based on different mechanisms for particle production in nuclear collisions. © 2016 CERN. © 2016 CERN, for the ALICE Collaboration. Published by the American Physical Society under the terms of the »http://creativecommons.org/licenses/by/3.0/» Creative Commons Attribution 3.0 License. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.

Centrality dependence of the nuclear modification factor of charged pions, kaons, and protons in Pb-Pb collisions at root s(NN)=2.76 TeV / Adam,J / PHYSICAL REVIEW C. - 2016.

Annotation:

Transverse momentum (p(T)) spectra of pions, kaons, and protons up to p(T) = 20 GeV/c have been measured in Pb-Pb collisions at root s(NN) = 2.76 TeV using the ALICE detector for six different centrality classes covering 0%-80%. The proton-to-pion and the kaon-to-pion ratios both show a distinct peak at p(T) approximate to 3 GeV/c in central Pb-Pb collisions that decreases for more peripheral collisions. For p(T) 10 GeV/c, the nuclear modification factor is found to be the same for all three particle species in each centrality interval within systematic uncertainties of 10%-20%. This suggests there is no direct interplay between the energy loss in the medium and the particle species composition in the hard core of the quenched jet. For p(T) 10 GeV/c, the data provide important constraints for models aimed at describing the transition from soft to hard physics.

Centrality evolution of the charged-particle pseudorapidity density over a broad pseudorapidity range in Pb-Pb collisions at root s(NN)=2.76TeV / Adam,J / PHYSICS LETTERS B. - 2016.

Annotation:

The centrality dependence of the charged-particle pseudorapidity density measured with ALICE in Pb-Pb collisions at root s(NN) = 2.76 TeV over a broad pseudorapidity range is presented. This Letter extends the previous results reported by ALICE to more peripheral collisions. No strong change of the overall shape of charged-particle pseudorapidity density distributions with centrality is observed, and when normalised to the number of participating nucleons in the collisions, the evolution over pseudorapidity with centrality is likewise small. The broad pseudorapidity range (-3.5 eta 5) allows precise estimates of the total number of produced charged particles which we find to range from 162 +/- 22(syst.) to 17170 +/- 770(syst.) in 80-90% and 0-5% central collisions, respectively. The total charged-particle multiplicity is seen to approximately scale with the number of participating nucleons in the collision. This suggests that hard contributions to the charged-particle multiplicity are limited. The results are compared to models which describe dN(ch)/d(eta) at mid-rapidity in the most central Pb-Pb collisions and it is found that these models do not capture all features of the distributions. (C) 2016 CERN for the benefit of the ALICE Collaboration. Published by Elsevier B.V.

Centrality, rapidity, and transverse momentum dependence of isolated prompt photon production in lead-lead collisions at root S-NN=2.76 TeV measured with the ATLAS detector / Aad,G / PHYSICAL REVIEW C. - 2016.

Annotation:

Prompt photon production in root S-NN = 2.76-TeV Pb + Pb collisions has been measured by the ATLAS experiment at the Large Hadron Collider using data collected in 2011 with an integrated luminosity of 0.14 nb(-1). Inclusive photon yields, scaled by the mean nuclear thickness function, are presented as a function of collision centrality and transverse momentum in two pseudorapidity intervals, vertical bar eta vertical bar 1.37 and 1.52

Characteristics of the Forbush decrease of 22 June 2015 measured by means of the muon hodoscope URAGAN / Barbashina,NS / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

Results of the studies of cosmic ray muon flux variations during the powerful Forbush effect registered by the muon hodoscope URAGAN on June 22, 2015 are presented. From the muon flux angular distribution, the dependence of the intensity decrease amplitude on the primary particle energy in the region above 10 GeV has been obtained. The changes of this dependence at different phases of the Forbush effect development have been studied. Based on the analysis of spatial and angular variations of the muon flux, the values of the local anisotropy vector parameters, as well as unique muon snapshots (muonographies) have been obtained. The characteristics of the heliospheric and magnetospheric disturbances during the considered event have been analyzed.

Characterization of the low-background Hamamatsu R11410-20 cryogenic PMTs for the RED100 detector / Akimov,DYu / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

The RED100 two-phase liquid xenon emission detector for neutrino coherent scattering experiments is equipped with 38 Hamamatsu R11410-20 photomultiplier tubes capable to operate at cryogenic temperatures and made of low background materials. A dedicated characterization procedure has been carried out for each PMT unit to be installed into the detector. The results presented here include single photoelectron analysis, gain curves for a wide range of the bias voltage values, data on dark count rate for 34 PMT samples. Peculiar noise characteristics of selected PMT units are analysed and discussed.

Charged-particle distributions in s=13 TeV pp interactions measured with the ATLAS detector at the LHC / Aad,G. / Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 2016.

Annotation:

Charged-particle distributions are measured in proton-proton collisions at a centre-of-mass energy of 13 TeV, using a data sample of nearly 9 million events, corresponding to an integrated luminosity of 170 μbsup-1/sup, recorded by the ATLAS detector during a special Large Hadron Collider fill. The charged-particle multiplicity, its dependence on transverse momentum and pseudorapidity and the dependence of the mean transverse momentum on the charged-particle multiplicity are presented. The measurements are performed with charged particles with transverse momentum greater than 500 MeV and absolute pseudorapidity less than 2.5, in events with at least one charged particle satisfying these kinematic requirements. Additional measurements in a reduced phase space with absolute pseudorapidity less than 0.8 are also presented, in order to compare with other experiments. The results are corrected for detector effects, presented as particle-level distributions and are compared to the predictions of various Monte Carlo event generators. © 2016 CERN for the benefit of the ATLAS Collaboration.

Mixed Pierce-two-stream instability development in an extraction system of a negative ion source / Chikhachev,A.S., Barminova,H.Y. // Review of Scientific Instruments. - 2016.

Annotation:

Mixed Pierce-two-stream instability may occur in an extraction system of a negative ion source based on a volume-produced plasma. The reasons for instability development are discussed. Analytically the conditions of unstable beam propagation are determined. The instability threshold is shown to be increased compared with the pure Pierce instability. The influence of inclined perturbations on the instability behavior is investigated. The numerical calculations are performed in COMSOL Multiphysics. The simulation results confirm the existence of such a mixed instability appearance that develops due to both the electrons of the external circuit and the background positive ions. © 2015 AIP Publishing LLC.

Oscillatory instability development in extraction system of a negative ion source / Chikhachev,A.S., Barminova,H.Y. // Review of Scientific Instruments. - 2016.

Annotation:

Conditions of oscillatory instability development in the extraction system of a negative hydrogen ion source based on a volume-produced plasma are studied. Such an ion source is characterized by the presence of the parent gas in the extraction system due to the leakage from the gas-discharge chamber. The secondary electrons in the area of the ion-optical system become the reason of oscillation appearance and possible beam current modulation. Analytically the range of the stable beam propagation is found. The instability increment is shown to be rather small. Maximum increment of the oscillations corresponds to the beam velocity equal to the thermal velocity of plasma electrons. The group velocity of the oscillations is close to the beam velocity so the oscillations are convective. Simulation of the low energy beam propagation is performed in COMSOL Multiphysics, the beam current modulation being observed. © 2015 AIP Publishing LLC.

Chiral extrapolation of the X(3872) binding energy / Baru,V / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

The role of pion dynamics in the X(3872) charmonium-like state is studied in the framework of a renormalisable effective quantum field theory approach and they are found to play a substantial role in the formation of the X. Chiral extrapolation from the physical point to unphysically large pion masses is performed and the results are confronted with the lattice predictions. The proposed approach overrides the gap between the lattice calculations and the physical limit in m(pi).

CNO and pep solar neutrino measurements and perspectives in Borexino / Davini,S / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

The detection of neutrinos emitted in the CNO reactions in the Sun is one of the ambitious goals of Borexino Phase-II. A measurement of CNO neutrinos would be a milestone in astrophysics, and would allow to solve serious issues in current solar models. A precise measurement of the rate of neutrinos from the pep reaction would allow to investigate neutrino oscillations in the MSW transition region. The pep and CNO solar neutrino physics, the measurement in Borexino Phase-I and the perspectives for the new phase are reviewed in this proceeding.

Combination of searches for WW, WZ, and ZZ resonances in pp collisions at s=8 TeV with the ATLAS detector / Aad,G. / Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 2016.

Annotation:

The ATLAS experiment at the CERN Large Hadron Collider has performed searches for new, heavy bosons decaying to WW, WZ and ZZ final states in multiple decay channels using 20.3 fbsup-1/sup of pp collision data at s=8 TeV. In the current study, the results of these searches are combined to provide a more stringent test of models predicting heavy resonances with couplings to vector bosons. Direct searches for a charged diboson resonance decaying to WZ in the ℓνℓsup'/supℓsup'/sup (ℓ=μ, e), ℓℓqq-, ℓνqq- and fully hadronic final states are combined and upper limits on the rate of production times branching ratio to the WZ bosons are compared with predictions of an extended gauge model with a heavy Wsup'/sup boson. In addition, direct searches for a neutral diboson resonance decaying to WW and ZZ in the ℓℓqq-, ℓνqq-, and fully hadronic final states are combined and upper limits on the rate of production times branching ratio to the WW and ZZ bosons are compared with predictions for a heavy, spin-2 graviton in an extended Randall-Sundrum model where the Standard Model fields are allowed to propagate in the bulk of the extra dimension. © 2016 CERN for the benefit of the ATLAS Collaboration.

Computational Validation of the Spectral Projection Method Using Models of the RBMK Critical Stand / Kachanov,V.M. / Atomic Energy. - 2016.

Annotation:

This article is devoted to the computational validation of algorithms for determining the reactivity on the basis of the spectral projection method and the method of reconstruction of the neutron fields. The determination of the efficacy of control organs on the RBMK critical stand on the basis of the indications of several intra-zone chambers is examined. A series of numerical experiments on the release of control rods and modeling of neutron-detector currents is conducted. The computed currents and a perturbed neutronphysical model based on the proposed algorithms are used to reconstruct the neutron fields and calculate the subcriticality of the RBMK stand. It is shown that the efficacy of control rods determined in this manner agrees with the exact values. © 2016 Springer Science+Business Media New York.

Computer analysis of nuclear track emulsion exposed to thermal neutrons and Cf source / Mamatkulov,KZ / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

Application of the nuclear track emulsion technique (NTE) in radioactivity and nuclear fission studies is discussed. It is suggested to use a HSP-1000 automated microscope for searching for a collinear cluster tri-partition of heavy nuclei implanted in NTE. Calibrations of cr-particles and ion ranges in a novel NTE are carried out. Surface exposures of NTE samples to a Cf-252 source started. Planar events containing fragments and long-range cr-particles as well as fragment triples only are studied. Splittings induced by thermal neutrons are studied in boron-enriched emulsion. Use of the image recognition program "ImageJ" for obtaining characteristics of individual events and for events from the large scan area is presented.

Conceptual approach to astronomical problems / Skvortsov,N.A. / Astrophysical Bulletin. - 2016.

Annotation:

New technical capabilities have brought about the sweeping growth of the amount of data acquired by the astronomers from observations with different instruments in various parts of the electromagnetic spectrum. We consider conceptual approach to be a promising tool to efficiently deal with these data. It uses problem domain knowledge to formulate the tasks and develop problem-solving algorithms and data analysis methods in terms of domain concepts without reference to particular data sources, and thereby allows solving certain problems in general form. We demonstrate the benefits of conceptual approach by using it to solve problems related to search for secondary photometric standard candidates, determination of galaxy redshifts, creation of a binary and multiple star repository based on inhomogeneous databases, and classification of eclipsing binaries.We formulate and solve these problems over specifications of astronomical knowledge units such as photometric systems, astronomical objects, multiple stars, etc., and define them in terms of the corresponding problem domains independently of the existing data resources. © 2016, Pleiades Publishing, Ltd.

Constraining the range of Yukawa gravity interaction from S2 star orbits II: Bounds on graviton mass / Jovanović,P./ Journal of Cosmology and Astroparticle Physics. - 2016.

Annotation:

Recently LIGO collaboration discovered gravitational waves [1] predicted 100 years ago by A. Einstein. Moreover, in the key paper reporting about the discovery, the joint LIGO & VIRGO team presented an upper limit on graviton mass such as mg < 1.2 × 10-22 eV [2] (see also more details in another LIGO paper [3] dedicated to a data analysis to obtain such a small constraint on a graviton mass). Since the graviton mass limit is so small the authors concluded that their observational data do not show violations of classical general relativity. We consider another opportunity to evaluate a graviton mass from phenomenological consequences of massive gravity and show that an analysis of bright star trajectories could bound graviton mass with a comparable accuracy with accuracies reached with gravitational wave interferometers and expected with forthcoming pulsar timing observations for gravitational wave detection. It gives an opportunity to treat observations of bright stars near the Galactic Center as a wonderful tool not only for an evaluation specific parameters of the black hole but also to obtain constraints on the fundamental gravity law such as a modifications of Newton gravity law in a weak field approximation. In particular, we obtain bounds on a graviton mass based on a potential reconstruction at the Galactic Center. © 2016 IOP Publishing Ltd and Sissa Medialab srl .

Correlations between jets and charged particles in PbPb and pp collisions at ssubNN/sub=2.76 TeV / TheCMScollaboration / Journal of High Energy Physics. - 2016.

Annotation:

Abstract: The quark-gluon plasma is studied via medium-induced changes to correlations between jets and charged particles in PbPb collisions compared to pp reference data. This analysis uses data sets from PbPb and pp collisions with integrated luminosities of 166 μbsup−1/sup and 5.3 pbsup−1/sup, respectively, collected at (Formula presented.) TeV. The angular distributions of charged particles are studied as a function of relative pseudorapidity (Δη) and relative azimuthal angle (Δϕ) with respect to reconstructed jet directions. Charged particles are correlated with all jets with transverse momentum (pT) above 120 GeV, and with the leading and subleading jets (the highest and second-highest in pT, respectively) in a selection of back-to-back dijet events. Modifications in PbPb data relative to pp reference data are characterized as a function of PbPb collision centrality and charged particle pT. A centrality-dependent excess of low-pT particles is present for all jets studied, and is most pronounced in the most central events. This excess of low-pT particles follows a Gaussian-like distribution around the jet axis, and extends to large relative angles of Δη ≈ 1 and Δϕ ≈ 1.[Figure not available: see fulltext.] © 2016, The Author(s).

Emergent gravity in the cubic tight-binding model of Weyl semimetal in the presence of elastic deformations / Cortijo,A., Zubkov,M.A. / Annals of Physics. - 2016.

Annotation:

We consider the tight-binding model with cubic symmetry that may be relevant for the description of a certain class of Weyl semimetals. We take into account elastic deformations of the semimetal through the modification of hopping parameters. This modification results in the appearance of emergent gauge field and the coordinate dependent anisotropic Fermi velocity. The latter may be interpreted as emergent gravitational field. © 2016 Elsevier Inc.

Sensitivity of the DANSS detector to short range neutrino oscillations / Danilov,M. / Nuclear and Particle Physics Proceedings. - 2016.

Annotation:

DANSS is a highly segmented 1 m3 plastic scintillator detector. Its 2500 scintillator strips have a Gd loaded reflective cover. Light is collected with 3 wave length shifting fibers per strip and read out with 50 PMTs and 2500 SiPMs. The DANSS will be installed under the industrial 3 GWth reactor of the Kalinin Nuclear Power Plant at distances varying from 9.7 m to 12.2 m from the reactor core. PMTs and SiPMs collect about 30 photo electrons per MeV distributed approximately equally between two types of the readout. Light collection non-uniformity across and along the strip is about ±13% from maximum to minimum. The resulting energy resolution is modest, σ/E=15% at 5 MeV. This leads to a smearing of the oscillation pattern comparable with the smearing due to the large size of the reactor core. Nevertheless because of the large counting rate (~10000/day), small background (< 1%) and good control of systematic uncertainties due to frequent changes of positions, the DANSS is quite sensitive to reactor antineutrino oscillations to hypothetical sterile neutrinos with a mass in eV ballpark suggested recently to explain a so-called reactor anomaly. DANSS will have an elaborated calibration system. The high granularity of the detector allows calibration of every strip with about 40 thousand cosmic muons every day. The expected systematic effects do not reduce much the sensitivity region. Tests of the detector prototype DANSSino demonstrated that in spite of a small size (4% of DANSS), it is quite sensitive to reactor antineutrinos, detecting about 70 Inverse Beta Decay events per day with the signal-to-background ratio of about unity. The prototype tests have demonstrated feasibility to reach the design performance of the DANSS detector. © 2015 Elsevier B.V.

Detection of thermal neutrons with the PRISMA-YBJ array in extensive air showers selected by the ARGO-YBJ experiment / Bartoli,B. / Astroparticle Physics. - 2016.

Annotation:

We report on a measurement of thermal neutrons, generated by the hadronic component of extensive air showers (EAS), by means of a small array of EN-detectors developed for the PRISMA project (PRImary Spectrum Measurement Array), novel devices based on a compound alloy of ZnS(Ag) and sup6/supLiF. This array has been operated within the ARGO-YBJ experiment at the high altitude Cosmic Ray Observatory in Yangbajing (Tibet, 4300 m a.s.l.). Due to the tight correlation between the air shower hadrons and thermal neutrons, this technique can be envisaged as a simple way to estimate the number of high energy hadrons in EAS. Coincident events generated by primary cosmic rays of energies greater than 100 TeV have been selected and analyzed. The EN-detectors have been used to record simultaneously thermal neutrons and the air shower electromagnetic component. The density distributions of both components and the total number of thermal neutrons have been measured. The correlation of these data with the measurements carried out by ARGO-YBJ confirms the excellent performance of the EN-detector. © 2016 Elsevier B.V.

Detector station and registering system of the NEVOD-EAS array cluster / Chiavassa,A / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

The design features of the detector stations of the cluster type shower array NEVOD-EAS which is now under construction on the basis of the Unique Scientific Facility `Experimental complex NEVOD', as well as the operation principle of the cluster registering system are discussed.

Deuteron spectrum measurements under radiation belt with PAMELA instrument / Adriani,O. / Nuclear and Particle Physics Proceedings. - 2016.

Annotation:

In this work the results of data analysis of the deuteron albedo radiation obtained in the PAMELA experiment are presented. PAMELA is an international space experiment carried out on board of the satellite Resurs DK-1. The high precision detectors allow to register and identify cosmic ray particles in a wide energy range. The albedo deuteron spectrum in the energy range 70 - 600 MeV/nucleon has been measured. © 2015 Elsevier B.V.

Development of a Computational Reactor Model in the IR Program Based on Experimental Data on Xenon Power Oscillations / Aver’yanova,S.P. / Atomic Energy. - 2016.

Annotation:

A method of improving the computational reactor model in the IR program on the basis of the experimental data on the xenon power oscillations is presented. It is concluded on the basis of the deviation of the computed axial offset from experiment that the program requires adjustment. The program was modernized by replacing the dependence of the thermophysical parameters of the core on the specific rate of power release by solving the heat-conduction and heat-and-mass transfer equations. This is accomplished by means of the method and software used in the NOSTRA computer code, which were additionally improved by taking account of the influence of structural changes in the fuel on the thermal conductivity. © 2016 Springer Science+Business Media New York.

Development of event reconstruction algorithm for full-body gamma-camera based on SiPMs / Philippov,DE / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

The gamma-camera is the detector for nuclear medical imaging where the photomultiplier tubes (PMTs) could be replaced by the silicon photomultipliers (SiPMs). Common systems have the energy resolution about 10% and intrinsic spatial resolution about 3 mm (FWHM). In order to achieve the requirement energy and spatial resolution the classical Anger's logic should be modified. In case of a standard monolithic thallium activated sodium iodide scintillator (500x400x10 mm(3)) and SiPM readout it could be done with identification of the clusters. We show that this approach has a good results with the simulated data.

Development of scanning technique for sTGC detectors production quality control / Konovalov,SP / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

The innermost station of the ATLAS muon end-cap system will be replaced during the forthcoming Phase-I upgrade of the ATLAS detector. The small-strip Thin Gap Chambers (sTGC) are supposed to operate at harsh radiation conditions of super LHC. X-ray scanning technique for production quality control is proposed to ensure long-term reliability of these chambers. It allows to reveal different types of technological defects critical for sTGC chambers operation.

DHCAL with minimal absorber: Measurements with positrons / Freund,B. / Journal of Instrumentation. - 2016.

Annotation:

In special tests, the active layers of the CALICE Digital Hadron Calorimeter prototype, the DHCAL, were exposed to low energy particle beams, without being interleaved by absorber plates. The thickness of each layer corresponded approximately to 0.29 radiation lengths or 0.034 nuclear interaction lengths, defined mostly by the copper and steel skins of the detector cassettes. This paper reports on measurements performed with this device in the Fermilab test beam with positrons in the energy range of 1 to 10 GeV. The measurements are compared to simulations based on GEANT4 and a standalone program to emulate the detailed response of the active elements. © 2016 IOP Publishing Ltd and Sissa Medialab srl.

Differential studies of inclusive J/psi and psi (2S) production at forward rapidity in Pb-Pb collisions at root s(NN)=2:76 TeVe / Adam,J / JOURNAL OF HIGH ENERGY PHYSICS. - 2016.

Annotation:

The production of J/psi and psi (2S) was studied with the ALICE detector in Pb-Pb collisions at the LHC. The measurement was performed at forward rapidity (2.5 y 4) down to zero transverse momentum (p(T)) in the dimuon decay channel. Inclusive J/psi yields were extracted in different centrality classes and the centrality dependence of the average p(T) is presented. The J/psi suppression, quantified with the nuclear modification factor (R-AA), was measured as a function of centrality, transverse momentum and rapidity. Comparisons with similar measurements at lower collision energy and theoretical models indicate that the J/psi production is the result of an interplay between color screening and recombination mechanisms in a deconfined partonic medium, or at its hadronization. Results on the psi(2S) suppression are provided via the ratio of psi(2S) over J/psi measured in pp and Pb-Pb collisions.

Digital trigger system for the RED-100 detector based on the unit in VME standard / Akimov,DYu// INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

The system for forming a trigger for the RED-100 liquid xenon detector has been developed. The trigger can be generated for all types of events required to calibrate the detector and data acquisition, including events with one ionization electron. The system has an event detection mechanism where each event is assigned with the timestamp and event type. The trigger system is required in the systems searching for rare events to keep only the necessary information from the ADC array. The characteristics and implementation of the trigger system that provides high efficiency operation even at low-energy events have been described.

Dijet production in √s=7 TeV pp collisions with large rapidity gaps at the ATLAS experiment / Aad,G. / Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 2016.

Annotation:

A 6.8 nbsup-1/sup sample of pp collision data collected under low-luminosity conditions at s=7TeV by the ATLAS detector at the Large Hadron Collider is used to study diffractive dijet production. Events containing at least two jets with pT>20GeV are selected and analysed in terms of variables which discriminate between diffractive and non-diffractive processes. Cross sections are measured differentially in δηsupF/sup, the size of the observable forward region of pseudorapidity which is devoid of hadronic activity, and in an estimator, ξ~, of the fractional momentum loss of the proton assuming single diffractive dissociation (pp→pX). Model comparisons indicate a dominant non-diffractive contribution up to moderately large δηsupF/sup and small ξ~, with a diffractive contribution which is significant at the highest δηsupF/sup and the lowest ξ~. The rapidity-gap survival probability is estimated from comparisons of the data in this latter region with predictions based on diffractive parton distribution functions. © 2016 CERN for the benefit of the ATLAS Collaboration.

Direct photon production in Pb-Pb collisions at √sNN = 2.76 TeV / Adam,J. / Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 2016.

Annotation:

Direct photon production at mid-rapidity in Pb-Pb collisions at √sNN=2.76 TeV was studied in the transverse momentum range 0.9<pT<14 GeV/c. Photons were detected with the highly segmented electromagnetic calorimeter PHOS and via conversions in the ALICE detector material with the esup+/supesup-/sup pair reconstructed in the central tracking system. The results of the two methods were combined and direct photon spectra were measured for the 0-20%, 20-40%, and 40-80% centrality classes. For all three classes, agreement was found with perturbative QCD calculations for pT > 5 GeV/c. Direct photon spectra down to pT≈1 GeV/c could be extracted for the 20-40% and 0-20% centrality classes. The significance of the direct photon signal for 0.9<pT<2.1 GeV/c is 2.6σ for the 0-20% class. The spectrum in this pT range and centrality class can be described by an exponential with an inverse slope parameter of (297±12supstat/sup±41supsyst/sup) MeV. State-of-the-art models for photon production in heavy-ion collisions agree with the data within uncertainties. © 2016 CERN for the benefit of the ALICE Collaboration.

The theory of equivalence measures and stochastic theory of turbulence for non-isothermal flow on the flat plate / Dmitrenko,A.V. // International Journal of Fluid Mechanics Research. - 2016.

Annotation:

In accordance with a theory of equivalence measures, the systems of stochastic equations for energy, momentum and mass are applied to non-isothermal flows. The analytical dependencies for estimations of the critical Reynolds number and value of the critical point of regime change for non-isothermal and compressible flows are written. As an example, the classical flow of the Newtonian medium on the smooth flat plate is considered. © 2016 Begell House, Inc.

DETERMINATION OF CRITICAL REYNOLDS NUMBERS FOR NONISOTHERMAL FLOWS BY USING THE STOCHASTIC THEORIES OF TURBULENCE AND EQUIVALENT MEASURES / Dmitrenko,ArturV // HEAT TRANSFER RESEARCH. - 2016.

Annotation:

The theory of equivalent measures and systems of stochastic equations for nonisothermal continuous medium flow is applied. The analytical expressions of critical Reynolds numbers depending on the Eckert number and initial turbulence for nonisothermal and compressible Newtonian medium flows for a smooth fl at plate and a round tube are discussed. A comparison of the calculated values of the critical Reynolds numbers and experimental data is presented.

Physics at ILC / Drutskoy,AG / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

The physics case for the International Linear Collider (ILC) project is discussed. The project is proposed to be built in Japan and a final decision has to be taken in 2016 on a government level. The initial data taking with e(+)e(-) beams is planned at the center-of-mass energy of 500 GeV with following runs at 250 GeV and 350 GeV. Potential physics studies at ILC are discussed with a special attention to the measurements, which are expected to have a better sensitivity at ILC in respect to the LHC experiments.

Diffraction limit of the theory of multiple small-angle neutron scattering by a dense system of scatterers / Dzheparov,FS, Lvov,DV / JETP LETTERS. - 2016.

Annotation:

Multiple small-angle neutron scattering by a high-density system of inhomogeneities has been considered. A combined approach to the analysis of multiple small-angle neutron scattering has been proposed on the basis of the synthesis of the Zernike-Prince and Moli,re formulas. This approach has been compared to the existing multiple small-angle neutron scattering theory based on the eikonal approximation. This comparison has shown that the results in the diffraction limit coincide, whereas differences exist in the refraction limit because the latter theory includes correlations between successive scattering events. It has been shown analytically that the existence of correlations in the spatial position of scatterers results in an increase in the number of unscattered neutrons. Thus, the narrowing of spectra of multiple small-angle neutron scattering observed experimentally and in numerical simulation has been explained.

Effect of inelastic and elastic energy losses of Xe ions on the evolution of hydrogen blisters in silicon / Reutov,V.F. / Technical Physics. - 2016.

Annotation:

We analyze the effect of irradiation by heavy ions on the formation of blisters on the silicon surface preliminarily ion-doped with hydrogen. An attempt is made at differentiating inelastic and elastic processes of interaction between ions and Si atoms using bombardment of the sample with high-energy charged particles through a bent absorbing filter by varying the radiation doses and the energy of bombarding Xe ions. It is found that irrespective of specific ionization energy losses of heavy ions, the blister formation is completely suppressed in the zone of the inelastic interaction during postradiation annealing. Conversely, stimulated development of hydrogen porosity takes place at the same time in the zone of elastic interaction, which is manifested in the form of blisters and flaking. © 2016, Pleiades Publishing, Ltd.

Elliptic flow of muons from heavy-flavour hadron decays at forward rapidity in Pb-Pb collisions at √sNN = 2.76 TeV / Adam,J. / Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 2016.

Annotation:

The elliptic flow, v2, of muons from heavy-flavour hadron decays at forward rapidity (2.5<y<4) is measured in Pb-Pb collisions at sNN=2.76 TeV with the ALICE detector at the LHC. The scalar product, two- and four-particle Q cumulants and Lee-Yang zeros methods are used. The dependence of the v2 of muons from heavy-flavour hadron decays on the collision centrality, in the range 0-40%, and on transverse momentum, pT, is studied in the interval 3<pT<10 GeV/c. A positive v2 is observed with the scalar product and two-particle Q cumulants in semi-central collisions (10-20% and 20-40% centrality classes) for the pT interval from 3 to about 5 GeV/c with a significance larger than 3σ, based on the combination of statistical and systematic uncertainties. The v2 magnitude tends to decrease towards more central collisions and with increasing pT. It becomes compatible with zero in the interval 6<pT<10 GeV/c. The results are compared to models describing the interaction of heavy quarks and open heavy-flavour hadrons with the high-density medium formed in high-energy heavy-ion collisions. © 2015 CERN for the benefit of the ALICE Collaboration.

Dark matter distribution and annihilation at the Galactic center / Eroshenko,YuN, Dokuchaev,VI / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

We describe a promising method for measuring the total dark matter mass near a supermassive black hole at the Galactic center based on observations of nonrelativistic precession of the orbits of fast SO stars. An analytical expression for the precession angle has been obtained under the assumption of a power-law profile of the dark matter density. The awaited weighing of the dark matter at the Galactic center provides the strong constraints on the annihilation signal from the neuralino dark matter particle candidate. The mass of the dark matter necessary for the explanation of the observed excess of gamma-radiation owing to the annihilation of the dark matter particles has been calculated with allowance for the Sommerfeld effect.

Estimation of reliability of linear point structures revealed in two-dimensional distributions of experimental data / Falomkina,OV / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

In the experiments at the FOBOS spectrometer [1] dedicated to study the spontaneous fission of the 248Cm and 252Cf nuclei in the mass correlation distribution of fission fragments new unusual structures bounded by magic clusters were observed for the first time. The structures were interpreted as a manifestation of a new exotic decay called collinear cluster tri-partition (CCT). These pioneer results were confirmed and detailed later in the series of experiments at different time-of-flight spectrometers [2]. Interpretation of the results obtained needs estimation of the statistical reliability of the structures mentioned above. The report presents the results of the solution to the problem of statistical reliability estimation on the basis of morphological image analysis [3].

Evaluation of the Antiproton Flux from the Antineutrino Electron Scattering / Alekseev,VV / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

Recent experiments in high enegry cosmic ray physics, PAMELA and AMS-02, excite a new interest to the mechanisms of generation of galactic antiparticles. In spite of the fact that global picture coincides with the predictions of the standard model, there are some black spots stimulating scientists to involve into research a particularly new physics like dark matter. In the present work, we make an attempt to estimate the impact of standard neutrino processes into the total flux of secondary antiprotons detected by contemporary experiments.

Evaluation of the spectrometric and dose characteristics of neutron fields inside the Russian segment of the ISS by fission detectors / Shurshakov,V.A. / Cosmic Research. - 2016.

Annotation:

The results of measuring the dose and the energy spectrum of neutrons inside the Russian segment of the International Space Station (ISS) from March 21 until November 10, 2002 are presented. Statistically reliable results of measurement are obtained by using thorium- and uranium-based fission detectors with cadmium and boron filters. The kits of the detectors with filters have been arranged in three compartments within assembled passive detectors in the BRADOS space experiment. The ambient dose rate H* = 139 μSv day and an energy spectrum of neutrons in the range of 10sup–2/sup–10sup4/sup MeV is obtained as average for the ISS compartments and is compared with the measurements carried out inside the compartments of the MIR space station. Recommendations on how to improve the procedure for using the fission detectors to measure the characteristics of neutron fields inside the compartments of space stations are formulated. © 2016, Pleiades Publishing, Ltd.

Event generator tunes obtained from underlying event and multiparton scattering measurements / Khachatryan,V / European Physical Journal C. - 2016.

Annotation:

New sets of parameters (“tunes”) for the underlying-event (UE) modelling of the pythia8, pythia6 and herwig++ Monte Carlo event generators are constructed using different parton distribution functions. Combined fits to CMS UE proton–proton ( (Formula presented.) ) data at (Formula presented.) and to UE proton–antiproton ( (Formula presented.) ) data from the CDF experiment at lower (Formula presented.) , are used to study the UE models and constrain their parameters, providing thereby improved predictions for proton–proton collisions at 13 (Formula presented.). In addition, it is investigated whether the values of the parameters obtained from fits to UE observables are consistent with the values determined from fitting observables sensitive to double-parton scattering processes. Finally, comparisons are presented of the UE tunes to “minimum bias” (MB) events, multijet, and Drell–Yan ( (Formula presented.) lepton-antilepton+jets) observables at 7 and 8 (Formula presented.) , as well as predictions for MB and UE observables at 13 (Formula presented.). © 2016, CERN for the benefit of the CMS collaboration.

Event-shape engineering for inclusive spectra and elliptic flow in Pb-Pb collisions at root(NN)-N-S=2.76 TeV / Adam,J / PHYSICAL REVIEW C. - 2016.

Annotation:

We report on results obtained with the event-shape engineering technique applied to Pb-Pb collisions at root s(NN) = 2.76 TeV. By selecting events in the same centrality interval, but with very different average flow, different initial-state conditions can be studied. We find the effect of the event-shape selection on the elliptic flow coefficient v(2) to be almost independent of transverse momentum p(T), which is as expected if this effect is attributable to fluctuations in the initial geometry of the system. Charged-hadron, -pion, -kaon, and -proton transverse momentum distributions are found to be harder in events with higher-than-average elliptic flow, indicating an interplay between radial and elliptic flow.

Evidence for single top-quark production in the s-channel in proton-proton collisions at s=8 TeV with the ATLAS detector using the Matrix Element Method / Aad,G. / Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 2016.

Annotation:

This Letter presents evidence for single top-quark production in the s-channel using proton-proton collisions at a centre-of-mass energy of 8 TeV with the ATLAS detector at the CERN Large Hadron Collider. The analysis is performed on events containing one isolated electron or muon, large missing transverse momentum and exactly two b-tagged jets in the final state. The analysed data set corresponds to an integrated luminosity of 20.3 fbsup-1/sup. The signal is extracted using a maximum-likelihood fit of a discriminant which is based on the matrix element method and optimized in order to separate single-top-quark s-channel events from the main background contributions, which are top-quark pair production and W boson production in association with heavy-flavour jets. The measurement leads to an observed signal significance of 3.2 standard deviations and a measured cross-section of σs=4.8±0.8(stat.)-1.3+1.6(syst.) pb, which is consistent with the Standard Model expectation. The expected significance for the analysis is 3.9 standard deviations. © 2016 CERN for the benefit of the ATLAS Collaboration.

Excitation spectra of solitary waves in scalar field models with polynomial self-interaction / Gani,VA / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

We study excitations of solitary waves the kinks in scalar models with degree eight polynomial self-interaction in (1 + 1) dimensions. We perform numerical studies of scattering of two kinks with an exponential asymptotic off each other and analyse the occurring resonance phenomena. We connect these phenomena to the energy exchange between the translational and the vibrational modes of the colliding kinks. We also point out that the interaction of two kinks with power-law asymptotic can lead to a long-range interaction between the two kinks.

Experimental study of the possibility of 3D localization of the compact gamma-sources in soft tissues / Berdnikova,AK / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

To determine the depth of the area of radiopharmaceutical accumulation a method of simultaneous recording of two lines of gamma rays of different energies and quantitative comparison of the intensity of these lines on the surface of the patient's body is provided. Since the coefficient of linear absorption of gamma radiation in the medium depends not only on the characteristics of the medium, but also on the gamma radiation energy, the intensity of gammas of different energies is attenuated differently after passing through the same absorber layer (soft tissues). Thus, the quantitative comparison of the relative intensities of gamma lines on the surface of the patient's body allows to determine the depth of area of the accumulation of the radiopharmaceutical. The result is achieved by analyzing the energy spectrum of the source, obtained with a semiconductor spectrometer, by measuring the ratio of areas of the absorption peaks of the radioisotope and defining the depth of gamma source using the calibration dependence between the areas ratio and the medium layer thickness. The most widely used medical radioisotope technetium-99m has two gamma-lines - 140 keV and 18.5keV, which allows one to apply the proposed method to search for the sentinel lymph nodes and non-palpable malignant tumors in the soft tissues.

Experimental testing of heavy ions mass search procedure in the measurements with PIN diodes / Kamanin,DV / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

We discuss the quality of heavy ions (HI) mass reconstruction in the wide range of HI energies and masses using Si PIN diodes for measuring both energy and time-of-flight. The results are based on the experimental data obtained at the IC-100 accelerator in the Flerov Laboratory of the JINR (Dubna, Russia).

Extending the Higgs sector: an extra singlet / Godunov,S.I. / European Physical Journal C. - 2016.

Annotation:

An extension of the Standard Model with an additional Higgs singlet is analyzed. Bounds on singlet admixture for the 125 GeV h boson from electroweak radiative corrections and data on h production and decays are obtained. The possibility of double h production enhancement at 14 TeV LHC due to a heavy Higgs contribution is considered. © 2016, The Author(s).

Extraction of activation energies from temperature dependence of dark currents of SiPM / Engelmann,E / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

Despite several advantages of Silicon Photomultipliers (SiPM) over Photomultiplier Tubes (PMT) like the increased photon detection efficiency (PDE), the compact design and the insensitivity to magnetic fields, the dark count rate (DCR) of SiPM is still a large drawback. Decreasing of the SiPM dark count rate has become a modern task, which could lead to an enormous enhancement of the application range of this promising photo-detector. The main goal of this work is to gain initial information on the dark generation and identify the dominating contributions to dark currents. The chosen approach to fulfill this task is to extract characteristic activation energies of the contributing mechanisms from temperature dependent investigations of dark currents and DCR. Since conventional methods are not suited for a precise analysis of activation energies, a new method has to be developed. In this paper, first steps towards the development of a reliable method for the analysis of dark currents and dark events are presented.

Extraction of rare earth elements from hydrate-phosphate precipitates of apatite processing / Stepanova,O.B. / IOP Conference Series: Materials Science and Engineering. - 2016.

Annotation:

The features of extraction of rare earth elements (REE) were considered from hydrate-phosphate precipitates of REE of apatite processing by nitric acid technology. The preliminary purification of nitrate solution of REE from impurities of titanium, aluminum, iron, uranium and thorium was suggested to obtain stable solutions not forming precipitates. Washing the extract was recommended with the evaporated reextract that allows to obtain directly on the cascade of REE extraction the concentrated solutions suitable for the separation into groups by the extraction method. Technical decisions were suggested for the separation of REE in groups without the use of salting-out agent. © Published under licence by IOP Publishing Ltd.

Wear Resistance of Carbon Steels and Structure Parameters of Their Surface Layer After High Current Density Sliding / Fadin,V.V., Aleutdinova,M.I. // Russian Physics Journal. - 2016.

Annotation:

Dry sliding of carbon steels under the action of an AC current of a contact density higher than 100 A/cmsup2/sup is realized. It is shown that the contact layer is easily deteriorated in high-carbon steels. This becomes evident as lower wear resistance compared to that of low-carbon steels. There are signs of a developing liquid phase on the worn surface. Using the methods of Auger spectroscopy and X-ray diffraction analysis, it is demonstrated that a high content of carbon in the initial steel structure gives rise to formation of a large amount of γ-Fe (and)as well to a high concentration of carbon near the sliding surface. © 2016 Springer Science+Business Media New York.

Fast timing and trigger Cherenkov detector for collider experiments / Karavicheva,TL / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

Analysis of fast timing and trigger Cherenkov detector's design for its use in collider experiments is presented. Several specific requirements are taken into account - necessity of the radiator's placement as close to the beam pipe as possible along with the requirement of gapless (solid) radiator's design. Characteristics of the Cherenkov detector's laboratory prototype obtained using a pion beam at the CERN Proton Synchrotron are also presented, showing the possibility of obtaining sufficiently high geometrical efficiency along with good enough time resolution (50 ps sigma).

Features of re-entrant albedo deuteron trajectories in near Earth orbit with PAMELA experiment / Adriani,O / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

The results of trajectory reconstruction for re-entrant albedo deuteron fluxes obtained in the PAMELA experiment are presented in this work. PAMELA is an international experiment aimed on measurements of cosmic ray particle fluxes in wide energy range. In particular, analysis of PAMELA data gives possibility to identify deuterons. Classification of re-entrant albedo deuterons with energies from 70 to 400 MeV/nucleon depending on theirs reconstructed lifetimes and generation zones is presented here at first time.

Femto-vortex sheets and hyperon polarization in heavy-ion collisions / Baznat,M. / Physical Review C - Nuclear Physics. - 2016.

Annotation:

We study the structure of vorticity and hydrodynamic helicity fields in peripheral heavy-ion collisions using the kinetic quark-gluon string model. The angular momentum conservation within this model holds with a good accuracy. We observe the formation of specific toroidal structures of vorticity field (vortex sheets). Their existence is mirrored in the polarization of hyperons of the percent order. © 2016 American Physical Society.

Ferromagnetism of Mnsubx/subSisub1-x/sub(x ∼ 0.5) films grown in the shadow geometry by pulsed laser deposition method / Nikolaev,S.N. / AIP Advances. - 2016.

Annotation:

The results of a comprehensive study of magnetic, magneto-transport and structural properties of nonstoichiometric MnxSi1-x (x 0.51-0.52) films grown by the Pulsed Laser Deposition (PLD) technique onto Al2O3(0001) single crystal substrates at T = 340°C are present. A highlight of used PLD method is the non-conventional ("shadow") geometry with Kr as a scattering gas during the sample growth. It is found that the films exhibit high-temperature (HT) ferromagnetism (FM) with the Curie temperature TC ∼ 370 K accompanied by positive sign anomalous Hall effect (AHE); they also reveal the polycrystalline structure with unusual distribution of grains in size and shape. It is established that HT FM order is originated from the bottom interfacial self-organizing nanocrystalline layer. The upper layer adopted columnar structure with the lateral grain size ≥50 nm, possesses low temperature (LT) type of FM order with Tc 46 K and contributes essentially to the magnetization at T ≤ 50 K. Under these conditions, AHE changes its sign from positive to negative at T ≤ 30K. We attribute observed properties to the synergy of distribution of MnxSi1-x crystallites in size and shape as well as peculiarities of defect-induced FM order in shadow geometry grown polycrystalline MnxSi1-x (x ∼ 0.5) films. © 2016 Author(s).

First model-independent Dalitz analysis of B-0 - DK*(0), D - K-S(0)pi(+)pi(-) decay / Negishi,K / PROGRESS OF THEORETICAL AND EXPERIMENTAL PHYSICS. - 2016.

Annotation:

We report a measurement of the amplitude ratio r(S) of B-0 - (DK)-K-0*(0) and B-0 - (D) over bar K-0*(0) decays with a Dalitz analysis of D - K-S(0)pi(+)pi(-) decays, for the first time using a model-independent method. We set an upper limit r(S) 0.87 at the 68% confidence level, using the full data sample of 711 fb(-1) corresponding to 772 x 10(6) B(B)over bar pairs collected at the Upsilon(4S) resonance with the Belle detector at the KEKB e(+)e(-) collider. This result is obtained from observables x(-) = +0.4(-0.6-0.1)(+1.0+0.0) +/- 0.0, y(-) = -0.6(-1.0-0.0)(+0.8+0.1) +/- 0.1, x(+) = +0.1(-0.4-0.1)(+0.7+0.0) +/- 0.1, and y(+) = +0.3(-0.8-0.1)(+0.5+0.0) +/- 0.1, where x(+/-) = r(S) cos(delta(S) +/- phi(3)), y(+/-) = r(S) sin(delta(S) +/- phi(3)), and phi(3) (delta(S)) is the weak (strong) phase difference between B-0 - D0K*(0) and B-0 - (D) over bar K-0*(0).

First observation of the decay B-0 - psi(2S)pi(0) / Chobanova,V / PHYSICAL REVIEW D. - 2016.

Annotation:

We report a measurement of the B-0 - psi(2S)pi(0) branching fraction based on the full Upsilon(4S) data set of 772 x 10(6) B (B) over bar pairs collected by the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider. We obtain B(B-0 - psi(2S)pi(0)) = (1.17 +/- 0.17(stat) +/- 0.08(syst)) x 10(-5). The result has a significance of 7.2 standard deviations and is the first observation of the decay B-0 - psi(2S)pi(0).

First results of the CALICE SDHCAL technological prototype / TheCALICECollaboration / Journal of Instrumentation. - 2016.

Annotation:

The CALICE Semi-Digital Hadronic Calorimeter (SDHCAL) prototype, built in 2011, was exposed to beams of hadrons, electrons and muons in two short periods in 2012 on two different beam lines of the CERN SPS. The prototype with its 48 active layers, made of Glass Resistive Plate Chambers and their embedded readout electronics, was run in triggerless and power-pulsing mode. The performance of the SDHCAL during the test beam was found to be very satisfactory with an efficiency exceeding 90% for almost all of the 48 active layers. A linear response (within ± 5%) and a good energy resolution are obtained for a large range of hadronic energies (5-80 GeV) by applying appropriate calibration coefficients to the collected data for both the Digital (Binary) and the Semi-Digital (Multi-threshold) modes of the SDHCAL prototype. The Semi-Digital mode shows better performance at energies exceeding 30 GeV. © 2016 IOP Publishing Ltd and Sissa Medialab srl.

First results of the cosmic ray muon variation study by means of the scintillation muon hodoscope / Ampilogov,NV / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

The new scintillation muon hodoscope to study cosmic ray muon flux variations was created in MEPhI. The basic characteristics of the hodoscope (sensitivity area, precision of the muon track reconstruction, 'live' time etc.) are comparable with other hodoscopes (TEMP and URAGAN) of MEPhI. Modular design is a distinctive feature of the detector, supplying relativity easy transportability, and low maintenance requirements give a possibility of a longterm autonomic operation. First results of the cosmic ray muon variation study by means of the scintillation muon hodoscope are presented and discussed.

Formation of primary particles in stopped pion absorption reactions / Gurov,Y.B. / Bulletin of the Russian Academy of Sciences: Physics. - 2016.

Annotation:

The results from analyzing the yields of protons (p), deuterons (d), and tritons (t) formed in the absorption of stopped π– mesons by intranuclear clusters are presented. The contributions from cluster absorption to the production of hydrogen isotopes in stopped pion absorption reactions are determined. Phenomenological formulas are proposed for describing the mass number (A) dependences of the yields of the primary protons with ∼15% precision in the mass number range of 6 < A < 209 (and of the primary deuterons and tritons in the mass number range of 59 < A < 209). Evidence is observed of the constancy of the ratio between the elemental absorption widths for the absorption of pions by pp and pn pairs over the investigated range of mass numbers. © 2016, Allerton Press, Inc.

Forward-central two-particle correlations in p-Pb collisions at √sNN = 5.02 TeV / Adam,J. / Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 2016.

Annotation:

Two-particle angular correlations between trigger particles in the forward pseudorapidity range (2.5 |η| 4.0) and associated particles in the central range (|η| 1.0) are measured with the ALICE detector in p-Pb collisions at a nucleon-nucleon centre-of-mass energy of 5.02 TeV. The trigger particles are reconstructed using the muon spectrometer, and the associated particles by the central barrel tracking detectors. In high-multiplicity events, the double-ridge structure, previously discovered in two-particle angular correlations at midrapidity, is found to persist to the pseudorapidity ranges studied in this Letter. The second-order Fourier coefficients for muons in high-multiplicity events are extracted after jet-like correlations from low-multiplicity events have been subtracted. The coefficients are found to have a similar transverse momentum (pT) dependence in p-going (p-Pb) and Pb-going (Pb-p) configurations, with the Pb-going coefficients larger by about 16 ± 6%, rather independent of pT within the uncertainties of the measurement. The data are compared with calculations using the AMPT model, which predicts a different pT and η dependence than observed in the data. The results are sensitive to the parent particle v2 and composition of reconstructed muon tracks, where the contribution from heavy flavour decays is expected to dominate at pT2 GeV/c. © 2015 CERN for the benefit of the ALICE Collaboration.

SU(2)/SL(2) knot invariants and Kontsevich–Soibelman monodromies / Galakhov,D.M., Mironov,A.D., Morozov,A.Y. / Theoretical and Mathematical Physics(Russian Federation). - 2016.

Annotation:

We review the Reshetikhin–Turaev approach for constructing noncompact knot invariants involving Rmatrices associated with infinite-dimensional representations, primarily those constructed from the Faddeev quantum dilogarithm. The corresponding formulas can be obtained from modular transformations of conformal blocks as their Kontsevich–Soibelman monodromies and are presented in the form of transcendental integrals, where the main issue is working with the integration contours. We discuss possibilities for extracting more explicit and convenient expressions that can be compared with the ordinary (compact) knot polynomials coming from finite-dimensional representations of simple Lie algebras, with their limits and properties. In particular, the quantum A-polynomials and difference equations for colored Jones polynomials are the same as in the compact case, but the equations in the noncompact case are homogeneous and have a nontrivial right-hand side for ordinary Jones polynomials. © 2016, Pleiades Publishing, Ltd.

Gamma-quanta onboard identification in the GAMMA-400 experiment using the counting and triggers signals formation system / Arkhangelskaja,IV / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

GAMMA-400 (Gamma Astronomical Multifunctional Modular Apparatus) will be the new generation satellite gamma-observatory. Gamma-telescope GAMMA-400 consists of anticoincidence system (top and lateral sections - ACtop and AClat), the converter-tracker (C), time-of-flight system (2 sections S1 and S2), position-sensitive calorimeter CC1 makes of 2 strips layers and 2 layers of CsI(Tl) detectors, electromagnetic calorimeter CC2 composed of CsI(Tl) crystals, neutron detector ND, scintillation detectors of the calorimeter (S3 and S4) and lateral detectors of the calorimeter (LD). All detector systems ACtop, AClat, S1-S4, LD consist of two BC-408 based sensitive layers of 1 cm thickness each. Three apertures provide events registration both from upper and lateral directions. The main aperture provides the best angular (all strip layers information analysis) and energy (energy deposition in the all detectors studying) resolution. Gamma-telescope GAMMA-400 is optimized for the gamma-quanta and charged particles with energy 100 GeV detection with the best parameters in the main aperture. Triggers in the main aperture will be formed using information about particle direction provided by time of flight system and presence of charged particle or backsplash signal formed according to analysis of energy deposition in combination of both layers anticoincidence systems.top and AClat individual detectors. For double-layer ACtop taking into account both amplitude and temporal trigger marker onboard analysis only 2.8 % photons will be wrongly recognized as electrons or protons for 100 GeV particles. The part of charged particles mistakenly identified as gammas is similar to 10(-5) using described algorithms. For E similar to 3 GeV less than 3% photons will be wrongly recognized as charged particles and fraction of wrongly identified charged particles will be also similar to 10(-5). In the additional aperture the particles identification is provided by analysis of signals corresponding to energy deposition in the individual detectors S2, S3 and fast signals from CC1 individual detectors discriminators. Low energy (0.2 - 10 MeV) photons in the lateral aperture recognizing by using simple anticoincidence signals from the individual detectors of LD. Gamma-quanta of higher energies are identified using energy deposition in the individual detectors of S3, S4, LD and fast signals from CC2 individual detectors discriminators. The results of anticoincidence system individual detectors thresholds modelling are discussed.

Gamma-Spectrometric Determination of the Plutonium Mass in Containers / Pavlov,A.M. / Atomic Energy. - 2016.

Annotation:

A method is proposed for determining the mass and isotopic composition of the plutonium warehoused in containers at the RT-1 plant of the Industrial Association Mayak. A single measurement system with a detector based on ultrapure germanium is used for the measurements. The mass is determined according to the pulse count rate in 239Pu peaks. The correction for self-absorption of radiation in a container is determined by measuring the transmission of radiation emitted from an external source and by Monte Carlo calculations. Estimates show that the total error in determining the plutonium mass by the new method is 11% (P = 0.95). The method can be used to perform confirmatory measurements in the accounting and control system for nuclear materials. © 2016 Springer Science+Business Media New York.

Gas gain stabilisation in the ATLAS TRT detector / Mindur,B / JOURNAL OF INSTRUMENTATION. - 2016.

Annotation:

The ATLAS (one of two general purpose detectors at the LHC) Transition Radiation Tracker (TRT) is the outermost of the three tracking subsystems of the ATLAS Inner Detector. It is a large straw-based detector and contains about 350,000 electronics channels. The performance of the TRT as tracking and particularly particle identification detector strongly depends on stability of the operation parameters with most important parameter being the gas gain which must be kept constant across the detector volume. The gas gain in the straws can vary significantly with atmospheric pressure, temperature, and gas mixture composition changes. This paper presents a concept of the gas gain stabilisation in the TRT and describes in detail the Gas Gain Stabilisation System (GGSS) integrated into the Detector Control System (DCS). Operation stability of the GGSS during Run-1 is demonstrated.

Gas mixtures for quality control of the sTGC chambers / Konovalov,SP / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

sTGC chambers are designed to operate at super-LHC conditions and will be installed in place during Phase-I upgrade of the ATLAS muon spectrometer. These chambers will provide precise coordinate measurements of the charged particle tracks and level 1 trigger for high pT muons. It is critical for the ATLAS detector to ensure a robust operation of these chambers during entire sLHC period. A quality control procedure based on X-ray scanner is being developed. Choice of the active gas for these tests is a very important issue. On one hand it should allow to find different types of chamber production defects, on the other hand one has to be sure that found problems are essential for the detector operation in future. Studies of the operation of the sTGC chamber prototype under X-ray irradiation with two gas mixtures (n-pentane/CO2 and CO2) were performed. The prototype was irradiated by X-rays with energy up to 50 keV. Particular attention was paid to the study of the "hot" chamber regions.

Geo-neutrino results with Borexino / Roncin,R / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

Borexino is a liquid scintillator detector primary designed to observe solar neutrinos. Due to its low background level as well as its position in a nuclear free country, Italy, Borexino is also sensitive to geo-neutrinos. Borexino is leading this interdisciplinary field of neutrino geoscience by studying electron antineutrinos which are emitted from the decay of radioactive isotopes present in the crust and the mantle of the Earth. With 2056 days of data taken between December 2007 and March 2015, Borexino observed 77 antineutrino candidates. If we assume a chondritic Th/U mass ratio of 3.9, the number of geo-neutrino events is found to be 23.7(-5.7)(+6.5) (stat)(-0.6)(+0.9) (syst). With this measurement, Borexino alone is able to reject the null geo-neutrino signal at 5.9 a, to claim a geo-neutrino signal from the mantle at 98 % C.L. and to restrict the radiogenic heat production for U and Th between 23 and 36 TW.

Hyperinstantons, the Beltrami equation, and triholomorphic maps / Grassi,PA, Fre,P, Sorin,AS / FORTSCHRITTE DER PHYSIK-PROGRESS OF PHYSICS. - 2016.

Annotation:

We consider the Beltrami equation for hydrodynamics and we show that its solutions can be viewed as instanton solutions of a more general system of equations. The latter are the equations of motion for an sigma model on 4-dimensional worldvolume (which is taken locally HyperKahler) with a 4-dimensional HyperKahler target space. By means of the 4D twisting procedure originally introduced by Witten for gauge theories and later generalized to 4D sigma-models by Anselmi and Fre, we show that the equations of motion describe triholomophic maps between the worldvolume and the target space. Therefore, the classification of the solutions to the 3-dimensional Beltrami equation can be performed by counting the triholomorphic maps. The counting is easily obtained by using several discrete symmetries. Finally, the similarity with holomorphic maps for sigma on Calabi-Yau space prompts us to reformulate the problem of the enumeration of triholomorphic maps in terms of a topological sigma model.

Fermion scattering on deformed extra space / Grobov,AV, Dmitriev,AE, Rubin,SG / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

Fermions are considered in a multidimensional space with two extra dimensions. Fermion Lagrangian contains coupling to a metric of deformed extra space. We show that the point-like defect on a space with topology of sphere leads to fermion interaction with such defect and calculate cross section of a fermion scattering on such defect.

H, He, Li and Be Isotopes in the PAMELA-Experiment / Menn,W / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

On the 15th of June 2006, the PAMELA satellite-borne experiment was launched from the Baikonur cosmodrome and it has been collecting data since July 2006. The apparatus comprises a time-of-flight system, a silicon-microstrip magnetic spectrometer, a silicon-tungsten electromagnetic calorimeter, an anti-coincidence system, a shower tail counter scintillator and a neutron detector. The scientific objectives addressed by the mission are the measurement of the antiprotons and positrons spectra in cosmic rays, the hunt for antinuclei as well as the determination of light nuclei fluxes from hydrogen to oxygen in a wide energy range and with very high statistics. In this paper the identification capability for light nuclei isotopes using two different detector systems (Time-of-Flight and multiple dE/dx measurements in the calorimeter) and preliminary results of the isotopic ratios will be presented.

High-energy cosmic antiparticle excess vs. isotropic gamma-ray background problem in decaying dark matter Universe / Alekseev,VV / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

We are going to show that any conventional decaying dark matter model, providing an explanation of cosmic antiparticle excess observed by PAMELA and AMS-02, inevitably faces the contradiction with isotropic diffuse gamma-ray background, measured by FERMI/LAT.

High-voltage power supply with improved thermostability for Xenon gamma-ray spectrometer / Petrenko,D / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

In this article the high voltage power supply for xenon spectrometer is described. Result of time simulation for output voltage at different temperatures was shown. The experimental data is confirming results of the time simulations. The experimental data showed breadboard model provides a stability of voltage better than 1% of the generated voltage at different temperatures.

Extensive air showers, lightning, and thunderstorm ground enhancements / Hovsepyan,G., Kozliner,L., Chilingarian,A. / Astroparticle Physics. - 2016.

Annotation:

For lightning research, we monitor particle fluxes from thunderclouds, the so-called thunderstorm ground enhancements (TGEs) initiated by runaway electrons, and extensive air showers (EASs) originating from high-energy protons or fully stripped nuclei that enter the Earth's atmosphere. We also monitor the near-surface electric field and atmospheric discharges using a network of electric field mills. The Aragats "electron accelerator" produced several TGEs and lightning events in the spring of 2015. Using 1-s time series, we investigated the relationship between lightning and particle fluxes. Lightning flashes often terminated the particle flux; in particular, during some TGEs, lightning events would terminate the particle flux thrice after successive recovery. It was postulated that a lightning terminates a particle flux mostly in the beginning of a TGE or in its decay phase; however, we observed two events (19 October 2013 and 20 April 2015) when the huge particle flux was terminated just at the peak of its development. We discuss the possibility of a huge EAS facilitating lightning leader to find its path to the ground. © 2016 Elsevier B.V. All rights reserved.

Mount Aragats as a stable electron accelerator for atmospheric high-energy physics research / Hovsepyan,Gagik, Mnatsakanyan,Eduard, Chilingarian,Ashot / PHYSICAL REVIEW D. - 2016.

Annotation:

Observation of the numerous thunderstorm ground enhancements (TGEs), i.e., enhanced fluxes of electrons, gamma rays, and neutrons detected by particle detectors located on the Earth's surface and related to the strong thunderstorms above it, helped to establish a new scientific topic-high-energy physics in the atmosphere. Relativistic runaway electron avalanches (RREAs) are believed to be a central engine initiating high-energy processes in thunderstorm atmospheres. RREAs observed on Mount Aragats in Armenia during the strongest thunderstorms and simultaneous measurements of TGE electron and gamma-ray energy spectra proved that RREAs are a robust and realistic mechanism for electron acceleration. TGE research facilitates investigations of the long-standing lightning initiation problem. For the last 5 years we were experimenting with the "beams" of "electron accelerators" operating in the thunderclouds above the Aragats research station. Thunderstorms are very frequent above Aragats, peaking in May-June, and almost all of them are accompanied with enhanced particle fluxes. The station is located on a plateau at an altitude 3200 asl near a large lake. Numerous particle detectors and field meters are located in three experimental halls as well as outdoors; the facilities are operated all year round. All relevant information is being gathered, including data on particle fluxes, fields, lightning occurrences, and meteorological conditions. By the example of the huge thunderstorm that took place at Mount Aragats on August 28, 2015, we show that simultaneous detection of all the relevant data allowed us to reveal the temporal pattern of the storm development and to investigate the atmospheric discharges and particle fluxes.

Hydrodynamic helicity and strange hyperon polarization in heavy-ion collisions / Baznat,M / 15TH INTERNATIONAL CONFERENCE ON STRANGENESS IN QUARK MATTER (SQM2015). - 2016.

Annotation:

We study the P-odd effects related to the vorticity of the medium formed in noncentral heavy ion collisions. Using the kinetic Quark-Gluon String Model, we perform numerical simulations of the vorticity and hydrodynamical helicity for various atomic numbers, energies and centralities. We observe vortical structures typically occupying a relatively small fraction of the fireball volume. In the course of numerical simulations a noticeable hydrodynamic helicity was observed manifesting a specific mirror behaviour with respect to the reaction plane. The effect is maximal at the NICA and FAIR energy range.

Hydrogenation of Nd-Fe alloys under conditions of different pressure and hydrogen concentration / Buinovskiy,A. / Key Engineering Materials. - 2016.

Annotation:

The paper presents the research results of the process of hydride grinding of Nd-Fe alloys, which are used for solid-phase alloying of base magnetic alloys having Nd-Fe-B system in order to improve magnetic characteristics of rare-earth permanent magnets. Alloys having rare-earth metals including Nd-Fe can be produced with the help of the out-of-furnace fluoride technology designed by the authors of this article. Hydrogenation of Nd-Fe alloys is used at the stage of their grinding. It is determined by complexity of mechanical grinding of these alloys because of their tensility and high strength. The thermodynamics of the process of alloy hydrogenation is considered. The effects of hydrogen surplus, the process scale and the surface area of alloys on their hydrogenation rate are investigated. The paper also presents the results of metallographic and roentgen-phase analyses of the sample surfaces of alloys which were hydrogenated. The analysis of the specific surface area of the materials is given. © Copyright 2016 Trans Tech Publications Ltd, Switzerland.

Identification of boosted, hadronically decaying W bosons and comparisons with ATLAS data taken at √s = 8 TeV / AtlasCollaboration / European Physical Journal C. - 2016.

Annotation:

This paper reports a detailed study of techniques for identifying boosted, hadronically decaying W bosons using 20.3 fb (Formula presented.) of proton–proton collision data collected by the ATLAS detector at the LHC at a centre-of-mass energy (Formula presented.). A range of techniques for optimising the signal jet mass resolution are combined with various jet substructure variables. The results of these studies in Monte Carlo simulations show that a simple pairwise combination of groomed jet mass and one substructure variable can provide a 50 % efficiency for identifying W bosons with transverse momenta larger than 200 GeV while maintaining multijet background efficiencies of 2–4 % for jets with the same transverse momentum. These signal and background efficiencies are confirmed in data for a selection of tagging techniques. © 2016, CERN for the benefit of the ATLAS collaboration.

iDREAM: an industrial detector for nuclear reactor monitoring / Gribov,IV / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

Prototype of industrial reactor antineutrino detector iDREAM is dedicated for an experiment to demonstrate the possibility of remote monitoring of PWR reactor operational modes by neutrino method in real-time in order to avoid undeclared exposure modes for nuclear fuel and unauthorized removal of isotopes. The prototype detector was started up in 2014. To test the detector elements and components of electronics distilled water has been used as a target, which enables the use of Cerenkov radiation from cosmic muons as a physical signal. Also parallel measuring of the long-term stability has been doing for samples of liquid organic scintillator doped with gadolinium and synthesized by different methods.

Inclusive and differential measurements of the tt charge asymmetry in pp collisions at √s=8 TeV / Khachatryan,V. / Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 2016.

Annotation:

The tt- charge asymmetry is measured in proton-proton collisions at a centre-of-mass energy of 8 TeV. The data, collected with the CMS experiment at the LHC, correspond to an integrated luminosity of 19.7 fbsup-1/sup. Selected events contain an electron or a muon and four or more jets, where at least one jet is identified as originating from b-quark hadronization. The inclusive charge asymmetry is found to be 0.0010±0.0068 (stat)±0.0037 (syst). In addition, differential charge asymmetries as a function of rapidity, transverse momentum, and invariant mass of the tt- system are studied. For the first time at the LHC, the measurements are also performed in a reduced fiducial phase space of top quark pair production, with an integrated result of -0.0035±0.0072 (stat)±0.0031 (syst). All measurements are consistent within two standard deviations with zero asymmetry as well as with the predictions of the standard model. © 2016 CERN for the benefit of the CMS Collaboration.

Inclusive and exclusive measurements of B decays to χc1 and χc2 at Belle / Bhardwaj,V. / Physical Review D - Particles, Fields, Gravitation and Cosmology. - 2016.

Annotation:

We report inclusive and exclusive measurements for χc1 and χc2 production in B decays. We measure B(B→χc1X)=(3.03±0.05(stat)±0.24(syst))×10-3 and B(B→χc2X)=(0.70±0.06(stat)±0.10(syst))×10-3. For the first time, χc2 production in exclusive B decays in the modes B0→χc2π-K+ and B+→χc2π+π-K+ has been observed, along with first evidence for the B+→χc2π+KS0 decay mode. For χc1 production, we report the first observation in the B+→χc1π+π-K+, B0→χc1π+π-KS0 and B0→χc1π0π-K+ decay modes. Using these decay modes, we observe a difference in the production mechanism of χc2 in comparison to χc1 in B decays. In addition, we report searches for X(3872) and χc1(2P) in the B+→(χc1π+π-)K+ decay mode. The reported results use 772×106 BB-events collected at the (4S) resonance with the Belle detector at the KEKB asymmetric-energy e+e- collider. © 2016 American Physical Society.

Inclusive quarkonium production at forward rapidity in pp collisions at √s = 8 TeV TeV / Adam,J. / European Physical Journal C. - 2016.

Annotation:

We report on the inclusive production cross sections of (Formula presented.) , (Formula presented.) , (Formula presented.) (1S), (Formula presented.) (2S) and (Formula presented.) (3S), measured at forward rapidity with the ALICE detector in (Formula presented.) collisions at a center-of-mass energy (Formula presented.)  TeV. The analysis is based on data collected at the LHC and corresponds to an integrated luminosity of 1.23 pb (Formula presented.). Quarkonia are reconstructed in the dimuon-decay channel. The differential production cross sections are measured as a function of the transverse momentum (Formula presented.) and rapidity y, over the (Formula presented.) ranges (Formula presented.)  GeV/c for (Formula presented.) , (Formula presented.)  GeV/c for all other resonances, and for (Formula presented.). The cross sections, integrated over (Formula presented.) and y, and assuming unpolarized quarkonia, are (Formula presented.)   (Formula presented.) b, (Formula presented.)   (Formula presented.) b, (Formula presented.)  nb, (Formula presented.)  nb and (Formula presented.)  nb, where the first uncertainty is statistical and the second one is systematic. These values agree, within at most (Formula presented.) , with measurements performed by the LHCb collaboration in the same rapidity range. © 2016, CERN for the benefit of the ALICE collaboration.

Induction centrifugal surfacing of the charge based on tin bronze powders with the addition of finely dispersed boehmite / Sosnovskiy,I.A. / Welding International. - 2016.

Annotation:

The method of induction centrifugal surfacing of a charge based on tin bronze powders of medium dispersion with the addition of finely dispersed boehmite, which is an intermediate product in the production of the nanodispersed modification agent (α-Al2O3), is described. Its characteristic feature is that it can be produced in the surfacing conditions resulting in the chemical transformation of the intermediate product present in the charge to the nanodispersed modification agent followed by its uniform distribution in the liquid phase coating. The results of metallographic studies and tribotechnical tests of these coatings are presented. The experiments were carried out to determine the optimum (2–3%) boehmite content of the charge resulting in the highest parameters of antifriction and wear resistance properties of the coatings based on tin bronze after induction centrifugal surfacing. © 2016 Informa UK Limited, trading as Taylor & Francis Group.

Influence of digital processing on the noise levels of spectrometric system for xenon gamma-spectrometer / Petrenko,D / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

Shaping and digital processing of xenon gamma-spectrometer signals were considered. Digital processing influence on the energy resolution of the spectrometric system of xenon gamma-spectrometer was shown. The analysis of contributions to the energy resolution showed that the limit of improvement of the resolution by using of digital processing is reached almost.

Comparative analysis of CR-39 sensitivity for different sets of measurable track parameters / Inozemtsev,K.O., Kushin,V.V. / Radiation Measurements. - 2016.

Annotation:

In the present paper the sensitivity V of plastic nuclear track detectors CR-39 to the space radiation, accelerated heavy ions in wide LET range and α-particles is studied. Different approaches for V evaluation are considered and compared. Main attention is given to the method that is appropriate for the measurement of short range heavy secondaries of space radiation. Finally, the experimental verification of the designed V function is carried out via simulation of the secondaries with low energy α-particles in the vicinity of the Bragg peak. © 2016 Elsevier Ltd.

Interdisciplinary glossary - particle accelerators and medicine / Dmitrieva,VV / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

A general concept of a new interdisciplinary glossary, which includes particle accelerator terminology used in medicine, as well as relevant medical concepts, is presented. Its structure and usage rules are described. An example, illustrating the quickly searching technique of relevant information in this Glossary, is considered. A website address, where one can get an access to the Glossary, is specified. Glossary can be refined and supplemented.

Investigation of the dynamic range of calorimeter scintillation detector for space gamma-ray telescope / Runtso,MF / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

An arrangement of the GAMMA-400 space gamma-ray telescope that currently is under the ground testing, suggests implementation of fast two-layer calorimeter scintillation detector system S3 with large dynamic range for electromagnetic showers detection in the main operation mode of the device. The S3 constructive features are demonstrated. The experimental method and basic diagram of the ground prototype dynamic range investigation are described.

Investigation of the energy characteristics of EAS muon component with the NEVOD-DECOR setup / Mannocchi,G / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

Investigations of the energy characteristics of muon component with the increase of the primary cosmic rays energy can be a key to solving `muon puzzle' the problem of excess of EAS muons (observed in several experiments at high ALEPH, DELPHI and ultrahigh energies DECOR, Pierre Auger Observatory) in comparison with the expected flux. The measurements results of the energy deposit of inclined muon bundles in water depending on the zenith angle and the local density of muons are presented. As a measure of the energy deposit, the total number of photoelectrons registered by PMTS of the Cherenkov water calorimeter NEVOD was used. The local density of muons, which gives an estimate of the energy of primary particles was obtained from the data of coordinate-tracking detector DECOR. The experimental data are compared with the results of calculations based on simulations of the muon component of EAS by means of the CORSIKA code.

Estimation of the shear viscosity from 3FD simulations of Au + Au collisions at √ssubNN/sub = 3.3-39 GeV / Ivanov,Y.B., Soldatov,A.A. / European Physical Journal A. - 2016.

Annotation:

An effective shear viscosity in central Au+Au collisions is estimated in the range of incident energies (Formula Presented). The simulations are performed within a three-fluid model employing three different equations of state with and without the deconfinement transition. In order to estimate this effective viscosity, we consider the entropy produced in the 3FD simulations as if it is generated within the conventional one-fluid viscous hydrodynamics. It is found that the effective viscosity within the different considered scenarios is very similar at the expansion stage of the collision: as a function of temperature (T) the viscosity-to-entropy ratio behaves as (Formula Presented); as a function of the net-baryon density (Formula Presented), i.e. it is mainly determined by the density dependence of the entropy density. The above dependences take place along the dynamical trajectories of Au+Au collisions. At the final stages of the expansion the (Formula Presented)s values are ranged from (Formula Presented) at the highest considered energies to (Formula Presented) at the lowest ones. © 2016, The Author(s).

What can we learn from the directed flow in heavy-ion collisions at BES RHIC energies? / Ivanov,Y.B., Soldatov,A.A. / European Physical Journal A. - 2016.

Annotation:

Analysis of directed flow (v1) of protons, antiprotons and pions in heavy-ion collisions is performed in the range of collision energies (Formula presented.). Simulations have been done within a three-fluid model employing a purely hadronic equation of state (EoS) and two versions of the EoS with deconfinement transitions: a first-order phase transition and a smooth crossover transition. The crossover EoS is unambiguously preferable for the description of the most part of experimental data in this energy range. The directed flow indicates that the crossover deconfinement transition takes place in semicentral Au+Au collisions in a wide range of collision energies (Formula presented.). The obtained results suggest that the deconfinement EoS’s in the quark-gluon sector should be stiffer at high baryon densities than those used in the calculation. The latter finding is in agreement with that discussed in astrophysics. © 2016, SIF, Springer-Verlag Berlin Heidelberg.

Baryon stopping signal for mixed phase formation in HIC / Ivanov,YuB / 15TH INTERNATIONAL CONFERENCE ON STRANGENESS IN QUARK MATTER (SQM2015). - 2016.

Annotation:

It is argued that an irregularity in the baryon stopping is a natural consequence of onset of deconfinement occurring in the compression stage of a nuclear collision. It is an effect of the softest point inherent in an equation of state (EoS) with a deconfinement transition. In order to illustrate this effect, calculations within the three-fluid model were performed with three different EoS's: a purely hadronic EoS, an EoS with a first-order phase transition and that with a smooth crossover transition.

Estimation of the shear viscosity from 3FD simulations of Au plus Au collisions at root s(NN)=3.3-39 GeV / Ivanov,YuB, Soldatov,AA / EUROPEAN PHYSICAL JOURNAL A. - 2016.

Annotation:

An effective shear viscosity in central Au+Au collisions is estimated in the range of incident energies 3.3 GeV

J/psi production at low transverse momentum in p plus p and d plus Au collisions at root s(NN)=200 GeV / Adamczyk,L / PHYSICAL REVIEW C. - 2016.

Annotation:

We report on the measurement of J/psi production in the dielectron channel at midrapidity (vertical bar y vertical bar 1) in p + p and d + Au collisions at root s(NN) from the measured J/psi invariant cross section in p + p and d + Au collisions are evaluated and compared to similar measurements at other collision energies. The nuclear modification factor for J/psi is extracted as a function of pT and collision centrality in d + Au and compared to model calculations using the modified nuclear parton distribution function and a final-state J/psi nuclear absorption cross section.

The method of event selection for nuclei separation with the calorimeter in the PAMELA experiment / Karelin,AV, Likhacheva,VL, Voronov,SA / XVI WORKSHOP ON HIGH ENERGY SPIN PHYSICS (D-SPIN2015). - 2016.

Annotation:

Here we discuss a method for a study of the heavy nuclei cosmic ray composition. The method is based on a charge separation with the PAMELA calorimeter. The work is in progress now. The ability is presented to carry out measurements up to Fe and Ni. As a result we expect to get important data about the abundance of the chemical elements in the cosmic rays.

Technological Trends in the Optimization of Standard Procedures in the Production of High-Quality Oxide Functional Materials / Katsnel’son,L.M., Kerbel’,B.M. / Glass and Ceramics (English translation of Steklo i Keramika). - 2016.

Annotation:

The role of technological trends in the technologies used to increase product quality in real ceramic production is examined for the example of a unified principle of optimization. It is shown that the uniformity of the final microstructure of a polycrystalline material depends on the probability of reaching the requirements imposed by the principle of optimization on process stages such as synthesis and the formation and sintering of blanks. Ways to increase the quality and profitability of the manufacture of ceramic products intended for use under extreme conditions are examined for the example of the components of nuclear fuel. © 2016 Springer Science+Business Media New York

The development of cross disciplinary studies in cosmology and particle physics on the platform of a Scientific-Educational complex of Virtual Institute of Astroparticle physics (VIA) / Khlopov,MYu / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

The overview of the main problems and methods of cosmoparticle physics, studying fundamental relationship of micro- and macro-worlds, is accompanied by the demonstration of the facility of Virtual Institute of Astroparticle physics (VIA) activity as a well proven platform for scientific collaborative work and education at distance.

Kinetic and microstructural studies of thermal decomposition in uranium mononitride compacts subjected to heating in high-purity helium / Lunev,A.V. / Journal of Nuclear Materials. - 2016.

Annotation:

Although uranium mononitride has a high melting point (≈3100 K), it often decomposes well below this temperature. The threshold and kinetics of thermal decomposition depend on samples' chemical content and on gas environment. However, most experiments with uranium nitride samples were done so far in vacuum conditions and did not allow thorough examination of reaction kinetics at high temperatures. This research focuses on studying the different stages of thermal decomposition in uranium nitride samples subjected to heating in helium. Mass loss and thermal effects are identified with simultaneous thermal analysis (STA), while scanning electron microscopy (SEM) and X-ray diffraction (XRD) are used to register phase and compositional changes. Thermal decomposition in uranium nitride samples is found to be a multi-stage process with the final stage characterized by uranium vaporization. The results are useful for estimating the high-temperature behaviour of uranium nitride fuel during its fabrication and performance in some of Gen IV reactors. © 2016 Elsevier B.V. All rights reserved.

Liquid-xenon detector under the intensive pulse irradiation conditions / Kirsanov,MA / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

The effect of intense pulsed irradiation on the operation of the liquid xenon spectrometer was studied. The ionization chamber filled with liquid xenon was irradiated by bremsstrahlung pulses of the microtron. The pulse repetition rate was 400 Hz. The absorbed dose ranged from 10(-7) to 0.1 Gy per pulse. Stable operation of the liquid xenon spectrometer in the intervals between the pulses of the accelerator was shown for a long time.

Rotating cylindrical wormholes and energy conditions / Krechet,V.G., Bronnikov,K.A. / International Journal of Modern Physics A. - 2016.

Annotation:

We seek wormholes among rotating cylindrically symmetric configurations in general relativity. Exact wormhole solutions are presented with such sources of gravity as a massless scalar field, a cosmological constant, and a scalar field with an exponential potential. However, none of these solutions are asymptotically flat, which excludes the existence of wormhole entrances as local objects in our Universe. To overcome this difficulty, we try to build configurations with flat asymptotic regions using the cut-and-paste procedure: on both sides of the throat, a wormhole solution is matched to a properly chosen region of flat space-time at some surfaces ∑- and ∑+. It is shown, however, that if the source of gravity in the throat region is a scalar field with an arbitrary potential, then one or both thin shells appearing on ∑- and ∑+ inevitably violate the null energy condition. Thus, although rotating wormhole solutions are easily found without exotic matter, such matter is still necessary for obtaining asymptotic flatness. © 2016 World Scientific Publishing Company.

Measurement of the thermal coefficient of linear expansion on a speckle-interferometric dilatometer / Kruglov,A.B., Kruglov,V.B., Osintsev,A.V. / Instruments and Experimental Techniques. - 2016.

Annotation:

A design of the speckle-interferometric dilatometer intended for studying thermal expansion of solid bodies at temperatures of 20–100°C is described. The calibration results for the thermal coefficient of linear expansion of copper, Armco iron, and 12Kh18N10T steel samples are given. © 2016, Pleiades Publishing, Inc.

Separation of ions on the front of a shock wave in a multicomponent plasma / Kuratov,AS, Bychenkov,VYu, Glazyrin,SI / JETP LETTERS. - 2016.

Annotation:

The structure of a shock wave propagating in a plasma with two types of ions has been studied within the model of multifluid hydrodynamics based on the 13-moment system of Grad's equations. Although the averaged dynamics of the shock front coincides with the single-component variant of the average-ion model, its structure is different at a noticeable difference between charge-to-mass ratios of different ions, demonstrating their separation on the shock front. For the problem of inertial confinement fusion, the range of parameters for which such a separation is important, as well as physical processes determining the two-component structure of the shock front, has been established.

Light yield measurements of "finger" structured and unstructured scintillators after gamma and neutron irradiation / Afanasiev,S.V. / Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment. - 2016.

Annotation:

Plastic scintillators are often used as detectors in High Energy Physics (HEP), but have insufficient radiation hardness. Organization of better light collection inside a single detector may prolong operation life of scintillators. A finger-strip plastic scintillator option has many advantages to keep the excellent detector performance at high luminosity. Measurements assigned to show an advantage of a stripped detector vs. the un-stripped one in the range of increased absorbed doses and the smallest dose rates have been performed. This method has proved to be a good upgrade strategy. © 2016 Elsevier B.V. All rights reserved.

Light-quark mass behaviour of the X(3872) as a molecular state / Baru,V. / EPJ Web of Conferences. - 2016.

Annotation:

Chiral extrapolations of the binding energy of the X(3872) molecular state are investigated using an explicitly renormalizable framework free of finite cut-off artefacts. Insights into the binding mechanisms are discussed: if the X is less bound with the growing pion mass, its binding energy is governed by the explicit pion mass dependence from one-pion exchange; an opposite behaviour would indicate the importance of the pionmass dependent short-range interactions, in addition to pionic effects. The important role of the three-body DDπ dynamics is emphasised. © 2016 Owned by the authors, published by EDP Sciences.

Local heating of a medium in the nanovicinity of the Co-57 nucleus that underwent radioactive decay to Fe-57 / Byakov,VM / HIGH ENERGY CHEMISTRY. - 2016.

Annotation:

Process of formation of the Auger blob (nanosized cloud of two or three hundred of ion-electron pairs) around a Co-57 radioactive atom after E-capture followed by the emission of a cascade of Auger electrons by the daughter atom Fe-57 has been considered. The effect of local temperature elevation in the Auger blob caused by energy emission during ionization slowing down of Auger electrons and the secondary electrons generated by them is discussed. Some consequences of this effect have been noted.

Data acquisition system based on fast waveform digitizers for large neutrino detectors / Lukyanchenko,G, Litvinovich,E / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

For large volume neutrino and antineutrino detectors it is crucial to have an efficient data acquisition system capable of digitizing data from thousands of detection channels. Here we present a flexible DAQ system architecture consisting of a large number of fast waveform digitizers and configurable FPGA-based trigger logic. The current implementation of the system is functioning in the Borexino neutrino detector providing zero dead time spectroscopy data in the energy range from 1 up to 100 MeV. Acquisition complex in combination with our custom analysis software is successfully being used for registration of geoneutrinos, as well as search for neutrino signal from GRBs, solar netrino spectroscopy and other applications.

Study of needle morphometric indices in Scots pine in the remote period after the Chernobyl accident / Makarenko,ES, Geras'kin,SA, Oudalova,AA / RADIOPROTECTION. - 2016.

Annotation:

Biological effects in Scots pine populations experiencing chronic radiation exposure at doses up to 130 mGy per year as a result of the Chernobyl accident were studied in 2011 and 2013, using needle indices as endpoints. No relationships between the length, the mass of needles and the asymmetry in weight of paired needles and radiation exposure were revealed. The frequency of necrotic needles increases with the level of radiation exposure; however, the significance of these effects in different years was different. The index of fluctuating asymmetry in needle length significantly increases at annual doses of 90 and 130 mGy and correlates with the absorbed dose as well as Cs-137 and Sr-90 radionuclide activities in soils and cones at the study sites. The findings obtained are consistent with an international recommendation to consider radiation exposure of 100 mGy.y(-1) as a margin for biota safety in chronic irradiation.

Simulations of the cosmic-veto system for the COMET experiment / Markin,Oleg, Tarkovsky,Evgueny / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

In the COMET experiment searching for the muon-electron conversion not conserving lepton numbers, a scintillator-strip-based veto system will be used to prohibit the COMET detector from fake signals initiated by cosmic muons. In order to verify the efficiency of the system, we have built its computer model and carried out various simulations. To tune the model, experimentally measured data are utilized. The simulations give the inefficiency of the cosmic-muon registration being below 0.0001, which meets requirements of the experiment. In addition, simulations of neutrons originating from muon captures and traversing a shield beneath the cosmic-veto system have been carried out using the Geant4 toolkit. A Geant4 application has been written with an appropriate detector design and possible spectrum of neutrons' energy. Design of the shield has been optimized to ensure the time loss concerned with fake veto signals caused by the background neutrons is tolerable. Materials of shield's layers are chosen, and optimum thicknesses of the layers are computed.

Measurement conditions in the space experiment MONICA / Bakaldin,AV / XVI WORKSHOP ON HIGH ENERGY SPIN PHYSICS (D-SPIN2015). - 2016.

Annotation:

The present contribution is dedicated to the investigation of the background conditions for cosmic ray ion ionization state measurements in MONICA experiment [1]. The future experiment MONICA is aimed to study the cosmic ray ion fluxes from H till Ni in energy range 10-300 MeV/n by multilayer semiconductor telescope-spectrometer installed onboard satellite. The satellite orbit parameters (circular, altitude is about 600 km, polar) were chosen for the realization of the unique method for the measurement of the charge state of the ions with energies 10 MeV/n by using the Earth magnetic field as a separator of ion charge. The analysis of the background particle fluxes is presented taking into account the recent data of the satellite experiments and known AE-8, AP-8 models and elaborated the recommendations to improve the background conditions for the MONICA experiment.

Measurement of an Excess in the Yield of J/ψ at Very Low pT in Pb-Pb Collisions at s NN=2.76 TeV / Adam,J. / Physical Review Letters. - 2016.

Annotation:

We report on the first measurement of an excess in the yield of J/ψ at very low transverse momentum (pT0.3 GeV/c) in peripheral hadronic Pb-Pb collisions at sNN

Measurement of D*sup±/sup, Dsup±/sup and Dsubs/sub sup±/sup meson production cross sections in pp collisions at s√=7 TeV with the ATLAS detector / Aad,G. / Nuclear Physics B. - 2016.

Annotation:

The production of D*sup±/sup, Dsup±/sup and Ds sup±/sup charmed mesons has been measured with the ATLAS detector in pp collisions at s=7 TeV at the LHC, using data corresponding to an integrated luminosity of 280 nbsup-1/sup. The charmed mesons have been reconstructed in the range of transverse momentum 3.5<pT(D)<100 GeV and pseudorapidity |η(D)|<2.1. The differential cross sections as a function of transverse momentum and pseudorapidity were measured for D*sup±/sup and Dsup±/sup production. The next-to-leading-order QCD predictions are consistent with the data in the visible kinematic region within the large theoretical uncertainties. Using the visible D cross sections and an extrapolation to the full kinematic phase space, the strangeness-suppression factor in charm fragmentation, the fraction of charged non-strange D mesons produced in a vector state, and the total cross section of charm production at s√=7 TeV were derived. © 2016 The Authors.

Measurement of D0-D0 mixing and search for CP violation in D0→K+K-,π+π- decays with the full Belle data set / Staric,M. / Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 2016.

Annotation:

We report an improved measurement of D0D0 mixing and a search for CP violation in D0 decays to CP-even final states K+K- and π+π-. The measurement is based on the final Belle data sample of 976 fb-1. The results are yCP=(1.11±0.22±0.09)% and AΓ=(-0.03±0.20±0.07)%, where the first uncertainty is statistical and the second is systematic. © 2015 The Authors.

Measurement of differential and integrated fiducial cross sections for Higgs boson production in the four-lepton decay channel in pp collisions at √s = 7 and 8 TeV / TheCMScollaboration / Journal of High Energy Physics. - 2016.

Annotation:

Integrated fiducial cross sections for the production of four leptons via the H → 4ℓ decays (ℓ = e, μ) are measured in pp collisions at (Formula presented.) and 8TeV. Measurements are performed with data corresponding to integrated luminosities of 5.1 fbsup−1/sup at 7TeV, and 19.7 fbsup−1/sup at 8 TeV, collected with the CMS experiment at the LHC. Differential cross sections are measured using the 8 TeV data, and are determined as functions of the transverse momentum and rapidity of the four-lepton system, accompanying jet multiplicity, transverse momentum of the leading jet, and difference in rapidity between the Higgs boson candidate and the leading jet. A measurement of the Z → 4ℓ cross section, and its ratio to the H → 4ℓ cross section is also performed. All cross sections are measured within a fiducial phase space defined by the requirements on lepton kinematics and event topology. The integrated H → 4ℓ fiducial cross section is measured to be 0. 56− 0.44 sup+ 0.67/sup(stat)− 0.06 sup+ 0.21/sup(syst) fb at 7 TeV, and 1. 11− 0.35 sup+ 0.41/sup(stat)− 0.10 sup+ 0.14/sup(syst) fb at 8 TeV. The measurements are found to be compatible with theoretical calculations based on the standard model. © 2016, The Author(s).

Measurement of differential cross sections for Higgs boson production in the diphoton decay channel in pp collisions at √s = 8 TeV / Khachatryan,V. / European Physical Journal C. - 2016.

Annotation:

A measurement is presented of differential cross sections for Higgs boson (H) production in pp collisions at √s = 8TeV. The analysis exploits the H→γγ decay in data corresponding to an integrated luminosity of 19.7fbsup-1/sup collected by the CMS experiment at the LHC. The cross section is measured as a function of the kinematic properties of the diphoton system and of the associated jets. Results corrected for detector effects are compared with predictions at next-to-leading order and next-to-next-to-leading order in perturbative quantum chromodynamics, as well as with predictions beyond the standard model. For isolated photons with pseudorapidities |η|<2.5, and with the photon of largest and next-to-largest transverse momentum (pT supγ/sup) divided by the diphoton mass mγγ satisfying the respective conditions of pT supγ/sup/mγγ>1/3 and >1/4, the total fiducial cross section is 32±10fb. © 2016, CERN for the benefit of the CMS collaboration.

Measurement of Dsubs/sub sup+/sup production and nuclear modification factor in Pb-Pb collisions at √ssubNN/sub = 2.76 TeV / TheALICEcollaboration / Journal of High Energy Physics. - 2016.

Annotation:

The production of prompt Ds sup+/sup mesons was measured for the first time in collisions of heavy nuclei with the ALICE detector at the LHC. The analysis was performed on a data sample of Pb-Pb collisions at a centre-of-mass energy per nucleon pair, (Formula presented.) , of 2.76 TeV in two different centrality classes, namely 0–10% and 20–50%. Ds sup+/sup mesons and their antiparticles were reconstructed at mid-rapidity from their hadronic decay channel Ds sup+/sup → ϕπsup+/sup, with ϕ → Ksup−/supKsup+/sup, in the transverse momentum intervals 4 < pT < 12GeV/c and 6 < pT < 12 GeV/c for the 0–10% and 20–50% centrality classes, respectively. The nuclear modification factor RAA was computed by comparing the pT-differential production yields in Pb-Pb collisions to those in proton-proton (pp) collisions at the same energy. This pp reference was obtained using the cross section measured at (Formula presented.) TeV and scaled to (Formula presented.) TeV. The RAA of Ds sup+/sup mesons was compared to that of non-strange D mesons in the 10% most central Pb-Pb collisions. At high pT (8 < pT < 12 GeV/c) a suppression of the Ds sup+/sup-meson yield by a factor of about three, compatible within uncertainties with that of non-strange D mesons, is observed. At lower pT (4 < pT < 8 GeV/c) the values of the Ds sup+/sup-meson RAA are larger than those of non-strange D mesons, although compatible within uncertainties. The production ratios Ds sup+/sup/Dsup0/sup and Ds sup+/sup/Dsup+/sup were also measured in Pb-Pb collisions and compared to their values in proton-proton collisions. © 2016, The Author(s).

Measurement of electrons from heavy-flavour hadron decays in p-Pb collisions at √sNN=5.02TeV / Adam,J. / Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 2016.

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The production of electrons from heavy-flavour hadron decays was measured as a function of transverse momentum (pT) in minimum-bias p-Pb collisions at sNN=5.02 TeV using the ALICE detector at the LHC. The measurement covers the pT interval 0.5<pT<12 GeV/c and the rapidity range -1.065<ycms<0.135 in the centre-of-mass reference frame. The contribution of electrons from background sources was subtracted using an invariant mass approach. The nuclear modification factor RpPb was calculated by comparing the pT-differential invariant cross section in p-Pb collisions to a pp reference at the same centre-of-mass energy, which was obtained by interpolating measurements at s=2.76 TeV and s=7 TeV. The RpPb is consistent with unity within uncertainties of about 25%, which become larger for pT below 1 GeV/c. The measurement shows that heavy-flavour production is consistent with binary scaling, so that a suppression in the high-pT yield in Pb-Pb collisions has to be attributed to effects induced by the hot medium produced in the final state. The data in p-Pb collisions are described by recent model calculations that include cold nuclear matter effects. © 2015 CERN for the benefit of the ALICE Collaboration.

Measurement of jet charge in dijet events from root s=8 TeV pp collisions with the ATLAS detector / Aad,G / PHYSICAL REVIEW D. - 2016.

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The momentum-weighted sum of the charges of tracks associated to a jet is sensitive to the charge of the initiating quark or gluon. This paper presents a measurement of the distribution of momentum-weighted sums, called jet charge, in dijet events using 20.3 fb(-1) of data recorded with the ATLAS detector at root s = 8 TeV in pp collisions at the LHC. The jet charge distribution is unfolded to remove distortions from detector effects and the resulting particle-level distribution is compared with several models. The p(T) dependence of the jet charge distribution average and standard deviation are compared to predictions obtained with several leading-order and next-to-leading-order parton distribution functions. The data are also compared to different Monte Carlo simulations of QCD dijet production using various settings of the free parameters within these models. The chosen value of the strong coupling constant used to calculate gluon radiation is found to have a significant impact on the predicted jet charge. There is evidence for a pT dependence of the jet charge distribution for a given jet flavor. In agreement with perturbative QCD predictions, the data show that the average jet charge of quark-initiated jets decreases in magnitude as the energy of the jet increases.

Measurement of Long-Range Near-Side Two-Particle Angular Correlations in pp Collisions at root s=13 TeV / Khachatryan,V / PHYSICAL REVIEW LETTERS. - 2016.

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Results on two-particle angular correlations for charged particles produced in pp collisions at a center-of- mass energy of 13 TeV are presented. The data were taken with the CMS detector at the LHC and correspond to an integrated luminosity of about 270 nb(-1). The correlations are studied over a broad range of pseudorapidity (vertical bar eta vertical bar 2.4) and over the full azimuth (phi) as a function of charged particle multiplicity and transverse momentum (p(T)). In high-multiplicity events, a long-range (vertical bar Delta eta vertical bar 2.0), near-side (Delta phi approximate to 0) structure emerges in the two-particle Delta eta-Delta phi correlation functions. The magnitude of the correlation exhibits a pronounced maximum in the range 1.0 p(T) 2.0 GeV/c and an approximately linear increase with the charged particle multiplicity, with an overall correlation strength similar to that found in earlier pp data at root s

Measurement of Muon Antineutrino Oscillations with an Accelerator-Produced Off-Axis Beam / Abe,K. / Physical Review Letters. - 2016.

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T2K reports its first measurements of the parameters governing the disappearance of ν-μ in an off-axis beam due to flavor change induced by neutrino oscillations. The quasimonochromatic ν-μ beam, produced with a peak energy of 0.6 GeV at J-PARC, is observed at the far detector Super-Kamiokande, 295 km away, where the ν-μ survival probability is expected to be minimal. Using a data set corresponding to 4.01×1020 protons on target, 34 fully contained μ-like events were observed. The best-fit oscillation parameters are sin2(θ-23)=0.45 and |Δm-322|=2.51×10-3 eV2 with 68% confidence intervals of 0.38-0.64 and 2.26-2.80×10-3 eV2, respectively. These results are in agreement with existing antineutrino parameter measurements and also with the νμ disappearance parameters measured by T2K. © 2016 authors.

Measurement of Radon concentration by Xenon gamma-ray spectrometer for seismic monitoring of the Earth / Novikov,A / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

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A method for earthquake precursors search based on variations of Rn-222 concentration determined via intensity measurement of Rn-222 daughter nuclei gamma ray emission lines by means of xenon gamma-ray spectrometer is discussed. The equipment description as well as the first experimental data are presented.

Measurement of Solar pp-neutrino flux with Borexino: results and implications / Smirnov,OYu / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

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Measurement of the Solar pp-neutrino flux completed the measurement of Solar neutrino fluxes from the pp-chain of reactions in Borexino experiment. The result is in agreement with the prediction of the Standard Solar Model and the MSW/LMA oscillation scenario. A comparison of the total neutrino flux from the Sun with Solar luminosity in photons provides a test of the stability of the Sun on the 105 years time scale, and sets a strong limit on the power production by the unknown energy sources in the Sun.

Measurement of spin correlations in tt production using the matrix element method in the muon+jets final state in pp collisions at √s=8 TeV / Khachatryan,V. / Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 2016.

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The consistency of the spin correlation strength in top quark pair production with the standard model (SM) prediction is tested in the muon+jets final state. The events are selected from pp collisions, collected by the CMS detector, at a centre-of-mass energy of 8 TeV, corresponding to an integrated luminosity of 19.7 fbsup-1/sup. The data are compared with the expectation for the spin correlation predicted by the SM and with the expectation of no correlation. Using a template fit method, the fraction of events that show SM spin correlations is measured to be 0.72±0.08(stat)sup+0.15/sup -0.13(syst), representing the most precise measurement of this quantity in the muon+jets final state to date. © 2016 The Author.

Measurement of the centrality dependence of the charged-particle pseudorapidity distribution in proton–lead collisions at √ssubNN/sub = 5.02 TeV with the ATLAS detector / Aad,G. / European Physical Journal C. - 2016.

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The centrality dependence of the mean charged-particle multiplicity as a function of pseudorapidity is measured in approximately 1 (Formula presented.) b (Formula presented.) of proton–lead collisions at a nucleon–nucleon centre-of-mass energy of (Formula presented.)   (Formula presented.) using the ATLAS detector at the Large Hadron Collider. Charged particles with absolute pseudorapidity less than 2.7 are reconstructed using the ATLAS pixel detector. The p + Pb collision centrality is characterised by the total transverse energy measured in the Pb-going direction of the forward calorimeter. The charged-particle pseudorapidity distributions are found to vary strongly with centrality, with an increasing asymmetry between the proton-going and Pb-going directions as the collisions become more central. Three different estimations of the number of nucleons participating in the p + Pb collision have been carried out using the Glauber model as well as two Glauber–Gribov inspired extensions to the Glauber model. Charged-particle multiplicities per participant pair are found to vary differently for these three models, highlighting the importance of including colour fluctuations in nucleon–nucleon collisions in the modelling of the initial state of p + Pb collisions. © 2016, The Author(s).

Measurement of the charge asymmetry in highly boosted top-quark pair production in √s=8 TeV pp collision data collected by the ATLAS experiment / Aad,G. / Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 2016.

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In the pp→tt process the angular distributions of top and anti-top quarks are expected to present a subtle difference, which could be enhanced by processes not included in the Standard Model. This Letter presents a measurement of the charge asymmetry in events where the top-quark pair is produced with a large invariant mass. The analysis is performed on 20.3 fbsup-1/sup of pp collision data at √s=8TeV collected by the ATLAS experiment at the LHC, using reconstruction techniques specifically designed for the decay topology of highly boosted top quarks. The charge asymmetry in a fiducial region with large invariant mass of the top-quark pair (mtt>0.75 TeV) and an absolute rapidity difference of the top and anti-top quark candidates within -2<|yt|-|yt|<2 is measured to be 4.2±3.2%, in agreement with the Standard Model prediction at next-to-leading order. A differential measurement in three tt- mass bins is also presented. © 2016 CERN for the benefit of the ATLAS Collaboration.

Measurement of the charge asymmetry in top quark pair production in pp collisions at root s=8 TeV using a template method / Khachatryan,V / PHYSICAL REVIEW D. - 2016.

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The charge asymmetry in the production of top quark and antiquark pairs is measured in proton-proton collisions at a center-of-mass energy of 8 TeV. The data, corresponding to an integrated luminosity of 19.6 fb(-1), were collected by the CMS experiment at the LHC. Events with a single isolated electron or muon, and four or more jets, at least one of which is likely to have originated from hadronization of a bottom quark, are selected. A template technique is used to measure the asymmetry in the distribution of differences in the top quark and antiquark absolute rapidities. The measured asymmetry is A(c)(y) = [0.33 +/- 0.26(stat) +/- 0.33(syst)]%, which is the most precise result to date. The results are compared to calculations based on the standard model and on several beyond-the-standard-model scenarios.

Measurement of the charge asymmetry in top-quark pair production in the lepton-plus-jets final state in pp collision data at root s=8 TeV with the ATLAS detector / Aad,G / EUROPEAN PHYSICAL JOURNAL C. - 2016.

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This paper reports inclusive and differential measurements of the t (t) over bar charge asymmetry A(C) in 20.3 fb(-1) of root s = 8 TeV pp collisions recorded by the ATLAS experiment at the Large Hadron Collider at CERN. Three differential measurements are performed as a function of the invariant mass, transverse momentum and longitudinal boost of the t (t) over bar system. The t (t) over bar pairs are selected in the single-lepton channels (e or mu) with at least four jets, and a likelihood fit is used to reconstruct the t (t) over bar event kinematics. A Bayesian unfolding procedure is performed to infer the asymmetry at parton level from the observed data distribution. The inclusive t (t) over bar charge asymmetry is measured to be A(C) = 0.009 +/- 0.005 (stat. + syst.). The inclusive and differential measurements are compatible with the values predicted by the Standard Model.

Measurement of the correlation between the polar angles of leptons from top quark decays in the helicity basis at root s=7 TeV using the ATLAS detector / Aad,G / PHYSICAL REVIEW D. - 2016.

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A measurement of the correlations between the polar angles of leptons from the decay of pair-produced t and (t) over bar quarks in the helicity basis is reported, using proton-proton collision data collected by the ATLAS detector at the LHC. The dataset corresponds to an integrated luminosity of 4.6 fb(-1) at a center-of-mass energy of root s = 7 TeV collected during 2011. Candidate events are selected in the dilepton topology with large missing transverse momentum and at least two jets. The angles theta(1) and theta(2) between the charged leptons and the direction of motion of the parent quarks in the t (t) over bar rest frame are sensitive to the spin information, and the distribution of cos theta(1).cos theta(2) is sensitive to the spin correlation between the t and (t) over bar quarks. The distribution is unfolded to parton level and compared to the next-to-leading order prediction. A good agreement is observed.

Measurement of the CP-violating weak phase φsubs/sub and the decay width difference δΓc using the Bsubs/sub sup0/sup→J/ψφ(1020) decay channel in pp collisions at √ s=8 TeV / Khachatryan,V. / Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 2016.

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The CP-violating weak phase φs of the Bs0 meson and the decay width difference δΓs of the Bs0 light and heavy mass eigenstates are measured with the CMS detector at the LHC using a data sample of Bs0→J/ψφ(1020)→μ+μ-K+K- decays. The analysed data set corresponds to an integrated luminosity of 19.7fbsup-1/sup collected in pp collisions at a centre-of-mass energy of 8TeV. A total of 49 200 reconstructed Bs0 decays are used to extract the values of φs and δΓs by performing a time-dependent and flavour-tagged angular analysis of the μsup+/supμsup-/supKsup+/supKsup-/sup final state. The weak phase is measured to be φs=-0.075±0.097(stat)±0.031(syst) rad, and the decay width difference is δΓs=0.095±0.013(stat)±0.007(syst) pssup-1/sup. © 2016 CERN for the benefit of the CMS Collaboration.

Measurement of the dependence of transverse energy production at large pseudorapidity on the hard-scattering kinematics of proton-proton collisions at √s=2.76 TeV with ATLAS / Aad,G. / Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 2016.

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The relationship between jet production in the central region and the underlying-event activity in a pseudorapidity-separated region is studied in 4.0 pbsup-1/sup of s=2.76 TeV pp collision data recorded with the ATLAS detector at the LHC. The underlying event is characterised through measurements of the average value of the sum of the transverse energy at large pseudorapidity downstream of one of the protons, which are reported here as a function of hard-scattering kinematic variables. The hard scattering is characterised by the average transverse momentum and pseudorapidity of the two highest transverse momentum jets in the event. The dijet kinematics are used to estimate, on an event-by-event basis, the scaled longitudinal momenta of the hard-scattered partons in the target and projectile beam-protons moving toward and away from the region measuring transverse energy, respectively. Transverse energy production at large pseudorapidity is observed to decrease with a linear dependence on the longitudinal momentum fraction in the target proton and to depend only weakly on that in the projectile proton. The results are compared to the predictions of various Monte Carlo event generators, which qualitatively reproduce the trends observed in data but generally underpredict the overall level of transverse energy at forward pseudorapidity. © 2016 CERN for the benefit of the ATLAS Collaboration.

Measurement of the differential cross-section of highly boosted top quarks as a function of their transverse momentum in s =8 TeV proton-proton collisions using the ATLAS detector / Aad,G. / Physical Review D - Particles, Fields, Gravitation and Cosmology. - 2016.

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The differential cross-section for pair production of top quarks with high transverse momentum is measured in 20.3 fb-1 of proton-proton collisions at a center-of-mass energy of 8 TeV. The measurement is performed for tt¯ events in the lepton+jets channel. The cross-section is reported as a function of the hadronically decaying top quark transverse momentum for values above 300 GeV. The hadronically decaying top quark is reconstructed as an anti-kt jet with radius parameter R=1.0 and identified with jet substructure techniques. The observed yield is corrected for detector effects to obtain a cross-section at particle level in a fiducial region close to the event selection. A parton-level cross-section extrapolated to the full phase space is also reported for top quarks with transverse momentum above 300 GeV. The predictions of a majority of next-to-leading-order and leading-order matrix-element Monte Carlo generators are found to agree with the measured cross-sections. © 2016 CERN.

Measurement of the differential cross-sections of prompt and non-prompt production of J/psi and psi(2S) in pp collisions at root s=7 and 8 TeV with the ATLAS detector / Aad,G / EUROPEAN PHYSICAL JOURNAL C. - 2016.

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The production rates of prompt and non-prompt J/psi and psi(2S) mesons in their dimuon decay modes are measured using 2.1 and 11.4 fb(-1) of data collected with the ATLAS experiment at the Large Hadron Collider, in proton-proton collisions at root s = 7 and 8 respectively. Production cross-sections for prompt as well as non-prompt sources, ratios of psi(2S) to J/psi production, and the fractions of non-prompt production for J/psi and psi(2S) are measured as a function of meson transverse momentum and rapidity. The measurements are compared to theoretical predictions.

Measurement of the double-beta decay half-life and search for the neutrinoless double-beta decay of Ca-48 with the NEMO-3 detector / Arnold,R / PHYSICAL REVIEW D. - 2016.

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The NEMO-3 experiment at the Modane Underground Laboratory investigates the double-beta decay of Ca-48. Using 5.25 yr of data recorded with a 6.99 g sample of Ca-48, approximately 150 double-beta decay candidate events are selected with a signal-to-background ratio greater than 3. The half-life for the two-neutrino double-beta decay of Ca-48 is measured to be T-1/2(2v) = [6.4(-0.6)(+0.7)(stat)(-0.6)(+0.7)(syst)] x 10(19) yr. A search for neutrinoless double-beta decay of Ca-48 yields a null result, and a corresponding lower limit on the half-life is found to be T-1/2(0v) 2.0 x 10(22) yr at 90% confidence level, translating into an upper limit on the effective Majorana neutrino mass of m(beta beta) 6.0-26 eV, with the range reflecting different nuclear matrix element calculations. Limits are also set on models involving Majoron emission and right-handed currents.

Measurement of the inclusive jet cross section in pp collisions at √s = 2.76 TeV / CMS Collaboration, / European Physical Journal C. - 2016.

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The double-differential inclusive jet cross section is measured as a function of jet transverse momentum pT and absolute rapidity |y|, using proton-proton collision data collected with the CMS experiment at the LHC, at a center-of-mass energy of √s = 2.76 TeV and corresponding to an integrated luminosity of 5.43 pb-1. Jets are reconstructed within the pT range of 74 to 592 GeV and the rapidity range |y|<3.0. The reconstructed jet spectrum is corrected for detector resolution. The measurements are compared to the theoretical prediction at next-to-leading-order QCD using different sets of parton distribution functions. This inclusive cross section measurement explores a new kinematic region and is consistent with QCD predictions. © 2016, CERN for the benefit of the CMS collaboration.

Measurement of the lepton forward-backward asymmetry in B - X(s)l(+)l(-) decays with a sum of exclusive modes / Sato,Y / PHYSICAL REVIEW D. - 2016.

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We report the first measurement of the lepton forward-backward asymmetry A(FB) as a function of the squared four-momentum of the dilepton system, q(2), for the electroweak penguin process B - X(s)l(+)l(-) with a sum of exclusive final states, where l is an electron or a muon and X-s is a hadronic recoil system with an s quark. The results are based on a data sample containing 772 x 10(6) B (B) over bar pairs recorded at the gamma (4S) resonance with the Belle detector at the KEKB e(+)e(-) collider. A(FB) for the inclusive B - X(s)l(+)l(-) is extrapolated from the sum of 10 exclusive X-s states whose invariant mass is less than 2 GeV/c(2). For q(2) 10.2 GeV2/c(2), A(FB) 0 is excluded at the 2.3 sigma level, where sigma is the standard deviation. For q(2) 4.3 GeV2/c(2), the result is within 1.8 sigma of the standard model theoretical expectation.

Measurement of the muon neutrino inclusive charged-current cross section in the energy range of 1-3 / Abe,K. / Physical Review D - Particles, Fields, Gravitation and Cosmology. - 2016.

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We report a measurement of the νμ-nucleus inclusive charged-current cross section (=σcc) on iron using data from the INGRID detector exposed to the J-PARC neutrino beam. The detector consists of 14 modules in total, which are spread over a range of off-axis angles from 0° to 1.1°. The variation in the neutrino energy spectrum as a function of the off-axis angle, combined with event topology information, is used to calculate this cross section as a function of neutrino energy. The cross section is measured to be σcc(1.1 GeV)=1.10±0.15 (10-38 cm2/nucleon), σcc(2.0 GeV)=2.07±0.27 (10-38 cm2/nucleon), and σcc(3.3 GeV)=2.29±0.45 (10-38 cm2/nucleon), at energies of 1.1, 2.0, and 3.3 GeV, respectively. These results are consistent with the cross section calculated by the neutrino interaction generators currently used by T2K. More importantly, the method described here opens up a new way to determine the energy dependence of neutrino-nucleus cross sections. © 2016 authors. Published by the American Physical Society.

Measurement of the production cross-section of a single top quark in association with a W boson at 8 TeV with the ATLAS experiment / TheATLAScollaboration / Journal of High Energy Physics. - 2016.

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The cross-section for the production of a single top quark in association with a W boson in proton-proton collisions at √s = 8TeV is measured. The dataset corresponds to an integrated luminosity of 20.3 fbsup−1/sup, collected by the ATLAS detector in 2012 at the Large Hadron Collider at CERN. Events containing two leptons and one central b-jet are selected. The W t signal is separated from the backgrounds using boosted decision trees, each of which combines a number of discriminating variables into one classifier. Production of W t events is observed with a significance of 7.7σ. The cross-section is extracted in a profile likelihood fit to the classifier output distributions. The W t cross-section, inclusive of decay modes, is measured to be 23.0 ± 1.3(stat.)− 3.5 sup+ 3.2/sup(syst.)±1.1(lumi.) pb. The measured cross-section is used to extract a value for the CKM matrix element |Vtb| of 1.01 ± 0.10 and a lower limit of 0.80 at the 95% confidence level. The cross-section for the production of a top quark and a W boson is also measured in a fiducial acceptance requiring two leptons with pT> 25 GeV and |η| < 2.5, one jet with pT> 20 GeV and |η| < 2.5, and ET supmiss/sup > 20 GeV, including both W t and top-quark pair events as signal. The measured value of the fiducial cross-section is 0.85 ± 0.01(stat.)− 0.07 sup+ 0.07/sup(syst.)±0.03(lumi.) pb. © 2016, The Author(s).

Measurement of the top quark mass using charged particles in pp collisions at s =8 TeV / Khachatryan,V. / Physical Review D - Particles, Fields, Gravitation and Cosmology. - 2016.

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A novel technique for measuring the mass of the top quark that uses only the kinematic properties of its charged decay products is presented. Top quark pair events with final states with one or two charged leptons and hadronic jets are selected from the data set of 8 TeV proton-proton collisions, corresponding to an integrated luminosity of 19.7 fb-1. By reconstructing secondary vertices inside the selected jets and computing the invariant mass of the system formed by the secondary vertex and an isolated lepton, an observable is constructed that is sensitive to the top quark mass that is expected to be robust against the energy scale of hadronic jets. The main theoretical systematic uncertainties, concerning the modeling of the fragmentation and hadronization of b quarks and the reconstruction of secondary vertices from the decays of b hadrons, are studied. A top quark mass of 173.68±0.20(stat)-0.97+1.58(syst) GeV is measured. The overall systematic uncertainty is dominated by the uncertainty in the b quark fragmentation and the modeling of kinematic properties of the top quark. © 2016 CERN, for the CMS Collaboration. Published by the American Physical Society under the terms of the »http://creativecommons.org/licenses/by/3.0/» Creative Commons Attribution 3.0 License. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.

Measurement of the top quark mass using proton-proton data at root(s)=7 / Khachatryan,V / PHYSICAL REVIEW D. - 2016.

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A new set of measurements of the top quark mass are presented, based on the proton-proton data recorded by the CMS experiment at the LHC at root s = 8 TeV corresponding to a luminosity of 19.7 fb(-1). The top quark mass is measured using the lepton + jets, all-jets and dilepton decay channels, giving values of 172.35 +/- 0.16(stat) +/- 0.48(syst) GeV, 172.32 +/- 0.25(stat) +/- 0.59(syst) GeV, and 172.82 +/- 0.19(stat) +/- 1.22(syst) GeV, respectively. When combined with the published CMS results at s = 7 TeV, they provide a top quark mass measurement of 172.44 +/- 0.13(stat) +/- 0.47(syst) GeV. The top quark mass is also studied as a function of the event kinematical properties in the lepton + jets decay channel. No indications of a kinematic bias are observed and the collision data are consistent with a range of predictions from current theoretical models of t (t) over bar production.

Measurement of the Top Quark Pair Production Cross Section in Proton-Proton Collisions at root s=13 TeV / Khachatryan,V / PHYSICAL REVIEW LETTERS. - 2016.

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The top quark pair production cross section is measured for the first time in proton-proton collisions at root s = 13 TeV by the CMS experiment at the CERN LHC, using data corresponding to an integrated luminosity of 43 pb(-1). The measurement is performed by analyzing events with at least one electron and one muon of opposite charge, and at least two jets. The measured cross section is 746 +/- 58(stat) +/- 53(syst) +/- 36(lumi) pb, in agreement with the expectation from the standard model.

Measurement of the transverse momentum and phi(eta)*. distributions of Drell-Yan lepton pairs in proton-proton collisions at root s=8 TeV with the ATLAS detector / Aad,G / EUROPEAN PHYSICAL JOURNAL C. - 2016.

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Distributions of transverse momentum p(T)(ll) and the related angular variable phi(eta)*. of Drell-Yan lepton pairs are measured in 20.3 fb(-1) of proton-proton collisions at root s = 8 TeV with the ATLAS detector at the LHC. Measurements in electron-pair and muon-pair final states are corrected for detector effects and combined. Compared to previous measurements in proton-proton collisions at root s = 7 TeV, these new measurements benefit from a larger data sample and improved control of systematic uncertainties. Measurements are performed in bins of lepton-pair mass above, around and below the Z-boson mass peak. The data are compared to predictions from perturbative and resummed QCD calculations. For values of phi(eta)*. 1 the predictions from the Monte Carlo generator ResBos are generally consistent with the data within the theoretical uncertainties. However, at larger values of phi(eta)*. this is not the case. Monte Carlo generators based on the parton-shower approach are unable to describe the data over the full range of p(T)(ll) while the fixed-order prediction of Dynnlo falls below the data at high values of p(T)(ll). ResBos and the parton-shower Monte Carlo generators provide a much better description of the evolution of the phi(eta)*. and p(T)(ll) distributions as a function of lepton-pair mass and rapidity than the basic shape of the data.

Measurement of the Transverse Single-Spin Asymmetry in p ↑+p →w± /Z0 at RHIC / Adamczyk,L. / Physical Review Letters. - 2016.

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We present the measurement of the transverse single-spin asymmetry of weak boson production in transversely polarized proton-proton collisions at s=500 GeV by the STAR experiment at RHIC. The measured observable is sensitive to the Sivers function, one of the transverse-momentum-dependent parton distribution functions, which is predicted to have the opposite sign in proton-proton collisions from that observed in deep inelastic lepton-proton scattering. These data provide the first experimental investigation of the nonuniversality of the Sivers function, fundamental to our understanding of QCD. © 2016 American Physical Society.

Measurement of the ttЇ production cross section in the all-jets final state in pp collisions at √s = 8 TeV / Khachatryan,V. / European Physical Journal C. - 2016.

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The cross section for (Formula presented.) production in the all-jets final state is measured in pp collisions at a centre-of-mass energy of 8  (Formula presented.) at the LHC with the CMS detector, in data corresponding to an integrated luminosity of 18.4  (Formula presented.). The inclusive cross section is found to be (Formula presented.) (Formula presented.). The normalized differential cross sections are measured as a function of the top quark transverse momenta, (Formula presented.) , and compared to predictions from quantum chromodynamics. The results are reported at detector, parton, and particle levels. In all cases, the measured top quark (Formula presented.) spectra are significantly softer than theoretical predictions. © 2016, CERN for the benefit of the CMS collaboration.

Measurement of the ZZ Production Cross Section in pp Collisions at root s=13 TeV with the ATLAS Detector / Aad,G / PHYSICAL REVIEW LETTERS. - 2016.

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The ZZ production cross section in proton-proton collisions at 13 TeV center-of-mass energy is measured using 3.2 fb(-1) of data recorded with the ATLAS detector at the Large Hadron Collider. The considered Z boson candidates decay to an electron or muon pair of mass 66-116 GeV. The cross section is measured in a fiducial phase space reflecting the detector acceptance. It is also extrapolated to a total phase space for Z bosons in the same mass range and of all decay modes, giving 16.7(-2.0)(+2.2) (stat)(-0.7)(+0.9) (syst)(-0.7)(+1.0) (lumi) pb. The results agree with standard model predictions.

Measurement of top quark polarisation in t-channel single top quark production / TheCMScollaboration / Journal of High Energy Physics. - 2016.

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A first measurement of the top quark spin asymmetry, sensitive to the top quark polarisation, in t-channel single top quark production is presented. It is based on a sample of pp collisions at a centre-of-mass energy of 8 TeV corresponding to an integrated luminosity of 19.7 fbsup−1/sup. A high-purity sample of t-channel single top quark events with an isolated muon is selected. Signal and background components are estimated using a fit to data. A differential cross section measurement, corrected for detector effects, of an angular observable sensitive to the top quark polarisation is performed. The differential distribution is used to extract a top quark spin asymmetry of 0.26 ± 0.03(stat) ± 0.10(syst), which is compatible with a p-value of 4.6% with the standard model prediction of 0.44. © 2016, The Author(s).

Measurement of transverse momentum relative to dijet systems in PbPb and pp collisions at (Formula presented.) TeV / TheCMScollaboration / Journal of High Energy Physics. - 2016.

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Abstract: An analysis of dijet events in PbPb and pp collisions is performed to explore the properties of energy loss by partons traveling in a quark-gluon plasma. Data are collected at a nucleon-nucleon center-of-mass energy of 2.76 TeV at the LHC. The distribution of transverse momentum (pT) surrounding dijet systems is measured by selecting charged particles in different ranges of pT and at different angular cones of pseudorapidity and azimuth. The measurement is performed as a function of centrality of the PbPb collisions, the pT asymmetry of the jets in the dijet pair, and the distance parameter R used in the anti-kT jet clustering algorithm. In events with unbalanced dijets, PbPb collisions show an enhanced multiplicity in the hemisphere of the subleading jet, with the pT imbalance compensated by an excess of low-pT particles at large angles from the jet axes. © 2016, The Author(s).

MEASUREMENTS OF COSMIC-RAY HYDROGEN AND HELIUM ISOTOPES WITH THE PAMELA EXPERIMENT / Adriani,O / ASTROPHYSICAL JOURNAL. - 2016.

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The cosmic-ray hydrogen and helium (H-1, H-2, He-3, He-4) isotopic composition has been measured with the satellite-borne experiment PAMELA, which was launched into low-Earth orbit on board the Resurs-DK1 satellite on 2006 June 15. The rare isotopes H-2 and He-3 in cosmic rays are believed to originate mainly from the interaction of high-energy protons and helium with the galactic interstellar medium. The isotopic composition was measured between 100 and 1100 MeV/n for hydrogen and between 100 and 1400 MeV/n for helium isotopes using two different detector systems over the 23rd solar minimum from 2006 July to 2007 December.

Measurements of fiducial cross-sections for (Formula presented.) production with one or two additional b-jets in pp collisions at √s = 8 TeV using the ATLAS detector / Aad,G. / European Physical Journal C. - 2016.

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Fiducial cross-sections for tt¯ production with one or two additional b-jets are reported, using an integrated luminosity of 20.3 fb-1 of proton–proton collisions at a centre-of-mass energy of 8 TeV at the Large Hadron Collider, collected with the ATLAS detector. The cross-section times branching ratio for tt¯ events with at least one additional b-jet is measured to be 950 ± 70 (stat.) -190 +240 (syst.) fb in the lepton-plus-jets channel and 50 ± 10 (stat.) -10 +15 (syst.) fb in the eμ channel. The cross-section times branching ratio for events with at least two additional b-jets is measured to be 19.3 ± 3.5 (stat.) ± 5.7 (syst.) fb in the dilepton channel (eμ, μμ, and ee) using a method based on tight selection criteria, and 13.5 ± 3.3 (stat.) ± 3.6 (syst.) fb using a looser selection that allows the background normalisation to be extracted from data. The latter method also measures a value of 1.30 ± 0.33 (stat.) ± 0.28 (syst.)% for the ratio of tt¯ production with two additional b-jets to tt¯ production with any two additional jets. All measurements are in good agreement with recent theory predictions. © 2016, CERN for the benefit of the ATLAS collaboration.

Measurements of four-lepton production in pp collisions at √s = 8 TeV with the ATLAS detector / Aad,G. / Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 2016.

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The four-lepton (4ℓ, ℓ=e, μ) production cross section is measured in the mass range from 80 to 1000 GeV using 20.3 fb-1 of data in pp collisions at s=8 TeV collected with the ATLAS detector at the LHC. The 4ℓ events are produced in the decays of resonant Z and Higgs bosons and the non-resonant ZZ continuum originating from qq-, gg, and qg initial states. A total of 476 signal candidate events are observed with a background expectation of 26.2±3.6 events, enabling the measurement of the integrated cross section and the differential cross section as a function of the invariant mass and transverse momentum of the four-lepton system. In the mass range above 180 GeV, assuming the theoretical constraint on the qq- production cross section calculated with perturbative NNLO QCD and NLO electroweak corrections, the signal strength of the gluon-fusion component relative to its leading-order prediction is determined to be μgg=2.4±1.0 (stat.)±0.5 (syst.)±0.8 (theory). © 2015 CERN for the benefit of the ATLAS Collaboration.

Measurements of t(t)over-bar spin correlations and top quark polarization using dilepton final states in pp collisions at root s=8 TeV / Khachatryan,V / PHYSICAL REVIEW D. - 2016.

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Measurements of the top quark-antiquark (t (t) over bar) spin correlations and the top quark polarization are presented for t (t) over bar pairs produced in pp collisions at root s = 8 TeV. The data correspond to an integrated luminosity of 19.5 fb(-1) collected with the CMS detector at the LHC. The measurements are performed using events with two oppositely charged leptons (electrons or muons) and two or more jets, where at least one of the jets is identified as originating from a bottom quark. The spin correlations and polarization are measured from the angular distributions of the two selected leptons, both inclusively and differentially, with respect to the invariant mass, rapidity, and transverse momentum of the t (t) over bar system. The measurements are unfolded to the parton level and found to be in agreement with predictions of the standard model. A search for new physics in the form of anomalous top quark chromo moments is performed. No evidence of new physics is observed, and exclusion limits on the real part of the chromo-magnetic dipole moment and the imaginary part of the chromo-electric dipole moment are evaluated.

Measurements of the (10860) and (11020) resonances via σ (e+e- → (nS)π+π-) / Santel,D. / Physical Review D - Particles, Fields, Gravitation and Cosmology. - 2016.

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We report new measurements of the total cross sections for e+e-→(nS)π+π- (n=1, 2, 3) and e+e-→bb¯ from a high-luminosity fine scan of the region s=10.63-11.05 GeV with the Belle detector. We observe that the (nS)π+π- spectra have little or no nonresonant component and extract from them the masses and widths of (10860) and (11020) and their relative phase. We find M10860=(10891.1±3.2-1.7+0.6) MeV/c2 and Γ10860=(53.7-5.6 -5.4+7.1 +1.3) MeV and report first measurements M11020=(10987.5-2.5 -2.1+6.4 +9.0) MeV/c2, Γ11020=(61-19 -20+9 +2) MeV, and φ11020-φ10860=(-1.0±0.4-0.1+1.4) rad. © 2016 American Physical Society.

Measurements of the Higgs boson production and decay rates and coupling strengths using pp collision data at √S=7 and 8 TeV in the ATLAS experiment / Aad,G. / European Physical Journal C. - 2016.

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Combined analyses of the Higgs boson production and decay rates as well as its coupling strengths to vector bosons and fermions are presented. The combinations include the results of the analyses of the H → γγ, ZZ∗, WW∗, Zγ, bb, ττ and μμ decay modes, and the constraints on the associated production with a pair of top quarks and on the off-shell coupling strengths of the Higgs boson. The results are based on the LHC proton-proton collision datasets, with integrated luminosities of up to 4.7 fb-1 at √S =7 TeV and 20.3 fb-1 at √S = 8 TeV, recorded by the ATLAS detector in 2011 and 2012. Combining all production modes and decay channels, the measured signal yield, normalised to the Standard Model expectation, is 1.18+0.15 -0.14. The observed Higgs boson production and decay rates are interpreted in a leading-order coupling framework, exploring a wide range of benchmark coupling models both with and without assumptions on the Higgs boson width and on the Standard Model particle content in loop processes. The data are found to be compatible with the Standard Model expectations for a Higgs boson at a mass of 125.36 GeV for all models considered. © 2015, The Author(s).

Measurements of W(+/-)Z production cross sections in pp collisions at root s=8 TeV with the ATLAS detector and limits on anomalous gauge boson self-couplings / Aad,G / PHYSICAL REVIEW D. - 2016.

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This paper presents measurements of W(+/-)Z production in pp collisions at a center-of-mass energy of 8 TeV. The gauge bosons are reconstructed using their leptonic decay modes into electrons and muons. The data were collected in 2012 by the ATLAS experiment at the Large Hadron Collider and correspond to an integrated luminosity of 20.3 fb(-1). The measured inclusive cross section in the detector fiducial region is sigma W(+/-)Z - l'nu ll = 35.1 +/- 0.9(stat) +/- 0.8(sys) +/- 0.8(lumi) fb, for one leptonic decay channel. In comparison, the next-to-leading-order Standard Model expectation is 30.0 +/- 2.1 fb. Cross sections for W(+)Z and W(-)Z production and their ratio are presented as well as differential cross sections for several kinematic observables. Limits on anomalous triple gauge boson couplings are derived from the transverse mass spectrum of the W(+/-)Z system. From the analysis of events with a W and a Z boson associated with two or more forward jets an upper limit at 95% confidence level on the W(+/-)Z scattering cross section of 0.63 fb, for each leptonic decay channel, is established, while the Standard Model prediction at next-to-leading order is 0.13 +/- 0.01 fb. Limits on anomalous quartic gauge boson couplings are also extracted.

Measurements of Z gamma and Z gamma gamma production in pp collisions at root s=8 TeV with the ATLAS detector / Aad,G / PHYSICAL REVIEW D. - 2016.

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The production of Z bosons with one or two isolated high-energy photons is studied using pp collisions at root s = 8 TeV. The analyses use a data sample with an integrated luminosity of 20.3 fb(-1) collected by the ATLAS detector during the 2012 LHC data taking. The Z gamma and Z gamma gamma production cross sections are measured with leptonic (e(+) e(-), mu(+) mu(-), nu(nu) over bar) decays of the Z boson, in extended fiducial regions defined in terms of the lepton and photon acceptance. They are then compared to cross-section predictions from the Standard Model, where the sources of the photons are radiation off initial-state quarks and radiative Z-boson decay to charged leptons, and from fragmentation of final-state quarks and gluons into photons. The yields of events with photon transverse energy E-T 250 GeV from l(+) l(-) gamma events and with E-T 400 GeV from nu(nu) over bar gamma events are used to search for anomalous triple gauge-boson couplings ZZ gamma and Z gamma gamma. The yields of events with diphoton invariant mass m(gamma gamma) 200 GeV from l(+) l(-) gamma gamma events and with m(gamma gamma) 300 GeV from nu(nu) over bar gamma gamma events are used to search for anomalous quartic gauge-boson couplings ZZ gamma gamma and Z gamma gamma gamma. No deviations from Standard Model predictions are observed and limits are placed on parameters used to describe anomalous triple and quartic gauge-boson couplings.

On skew tau-functions in higher spin theory / Melnikov,D., Mironov,A., Morozov,A. / Journal of High Energy Physics. - 2016.

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Abstract: Recent studies of higher spin theory in three dimensions concentrate on Wilson loops in Chern-Simons theory, which in the classical limit reduce to peculiar corner matrix elements between the highest and lowest weight states in a given representation of SL(N). Despite these “skew” tau-functions can seem very different from conventional ones, which are the matrix elements between the two highest weight states, they also satisfy the Toda recursion between different fundamental representations. Moreover, in the most popular examples they possess simple representations in terms of matrix models and Schur functions. We provide a brief introduction to this new interesting field, which, after quantization, can serve as an additional bridge between knot and integrability theories. © 2016, The Author(s).

Method and Means for Monitoring the Spent-Fuel Pool Subcriticality at the Smolensk NPP / Geraskin,IN / ATOMIC ENERGY. - 2016.

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Research based on the pulsed neutron experiment method (alpha-method) of subcriticality monitoring of the spent fuel pool at the Smolensk NPP is presented. The procedure includes stationary and nonstationary neutron-physical calculations and measurements of the main characteristics of a subcritical multiplying system, which the spent-fuel pool is. A description of the STEPAN-KhOYaT software specially developed for the computational support of the pulsed experiment is given. The subcriticality for real loads of spent-fuel pools is calculated and measured using the procedure.

Method of incident low-energy gamma-ray direction reconstruction in the GAMMA-400 gamma-ray space telescope / Suchkov,SI / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

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The GAMMA-400 gamma-ray space-based telescope has as its main goals to measure cosmic gamma-ray fluxes and the electron-positron cosmic-ray component produced, theoretically, in dark-matter-particles decay or annihilation processes, to search for discrete gamma-ray sources and study them in detail, to examine the energy spectra of diffuse gamma-rays - both galactic and extragalactic - and to study gamma-ray bursts (GRBs) and gamma-rays from the active Sun. Scientific goals of GAMMA-400 telescope require fine angular resolution. The telescope is of a pair-production type. In the converter-tracker, the incident gamma-ray photon converts into electron-positron pair in the tungsten layer and then the tracks are detected by silicon-strip position-sensitive detectors. Multiple scattering processes become a significant obstacle in the incident-gamma direction reconstruction for energies below several gigaelectronvolts. The method of utilising this process to improve the resolution is proposed in the presented work.

Method to select gamma rays with energy above 50 GeV against a charge-particle background in the GAMMA-400 space telescope / Gusakov,YuV / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

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Studying high-energy (50 GeV) cosmic gamma radiation raises a problem of selection of neutral gamma rays from a background of charged particles. The problem is embarrassed by the backsplash effect. The backsplash consists, in the main, of low-energy (1MeV) secondary photons moving backwards and is produced by any high-energy gamma quantum. A charged-particle rejection method using the anticoincidence and time-of-flight systems is proposed. Charged-particle events are distinguished from those being triggered by high-energy gamma-rays producing backsplash. The method is based on the time separation of signals. It allows us to keep the gamma-ray detection efficiency high up to high energies.

Methods of Inspecting the Radioactive Contamination of Uranium-Graphite Reactor Masonry / Bushuev,A.V. / Atomic Energy. - 2016.

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One problem of decommissioning graphite reactors is the evaluation of the radioactive contamination of the graphite. The possible methods of determining the composition, contamination, and radionuclide concentration by means of laboratory analysis of graphite samples taken from the reactor masonry are examined. It is proposed that samples of graphite powder formed during repair work performed on RBMK masonry be used. Life tests have shown that since their operational stability in neutron and γ radiation fields is adequate CdZnTe detectors can be used to probe the channels in the reactor masonry. © 2016 Springer Science+Business Media New York.

Microstructural evolution of Fe-22%Cr model alloy under thermal ageing and ion irradiation conditions studied by atom probe tomography / Thuvander,M. / Journal of Nuclear Materials. - 2016.

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Nanostructure evolution during ion irradiation of two thermally aged binary Fee22Cr alloys has been investigated using atom probe tomography. Specimens aged at 500 °C for 50 and 200 h were irradiated by 5.6 MeV Fe ions at room temperature up to fluences of 0.3 × 10sup15/sup ions/cmsup2/sup and 1 × 10sup15/sup ions/cmsup2/sup. The effect of irradiation on the material nanostructure was examined at a depth of 1 μm from the irradiated surface. The analysis of Cr radial concentration functions reveals that dense α′-phase precipitates in the 200 h aged alloy become diffuse and thereby larger when subjected to irradiation. On the other hand, less Cr-enriched precipitates in the alloy aged for 50 h are less affected. The CreCr pair correlation function analysis shows that matrix inhomogeneity decreases under irradiation. Irradiation leads to a decrease in the number density of diffuse clusters, whereas in the case of well-developed precipitates it remains unchanged. © 2016 Published by Elsevier B.V.

Miniature gamma detector based on inorganic scintillator and SiPM / Dubinin,FA / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

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The miniature gamma counter based on a cylindrical LaBr3(Ce) crystal (5 mm diameter and 10 mm length) and SensL FC30035 silicon photomultiplier (SiPM) is introduced. The main counter characteristics such as relative efficiency, LaBr3(Ce) self-radioactivity and energy resolution are presented. Capability of using such detector for gamma spectrometry applications is discussed.

On elementary proof of AGT relations from six dimensions / Mironov,A., Morozov,A., Zenkevich,Y. / Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 2016.

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The actual definition of the Nekrasov functions participating in the AGT relations implies a peculiar choice of contours in the LMNS and Dotsenko-Fateev integrals. Once made explicit and applied to the original triply-deformed (6-dimensional) version of these integrals, this approach reduces the AGT relations to symmetry in q1,2,3, which is just an elementary identity for an appropriate choice of the integration contour (which is, however, a little non-traditional). We illustrate this idea with the simplest example of N=(1,1) U(1) SYM in six dimensions, however all other cases can be evidently considered in a completely similar way. © 2016 The Authors.

Universal Racah matrices and adjoint knot polynomials: Arborescent knots / Mironov,A, Morozov,A / PHYSICS LETTERS B. - 2016.

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By now it is well established that the quantum dimensions of descendants of the adjoint representation can be described in a universal form, independent of a particular family of simple Lie algebras. The Rosso-Jones formula then implies a universal description of the adjoint knot polynomials for torus knots, which in particular unifies the HOMFLY (SUN) and Kauffman (SON) polynomials. For E-8 the adjoint representation is also fundamental. We suggest to extend the universality from the dimensions to the Racah matrices and this immediately produces a unified description of the adjoint knot polynomials for all arborescent (double-fat) knots, including twist, 2-bridge and pretzel. Technically we develop together the universality and the "eigenvalue conjecture", which expresses the Racah and mixing matrices through the eigenvalues of the quantum R-matrix, and for dealing with the adjoint polynomials one has to extend it to the previously unknown 6 x 6 case. The adjoint polynomials do not distinguish between mutants and therefore are not very efficient in knot theory, however, universal polynomials in higher representations can probably be better in this respect. (C) 2016 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY license.

Bottomonium(-like) states at e(+)e(-) colliders / Mizuk,RV / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

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We review recent results on bottomonium(-like) states from e(+)e(-) colliders. They include energy scan of the e(+)e(-) annihilation cross sections into Upsilon(nS)pi(+)pi(-) and h(b)(nP)pi(+)pi(-) final states, studies of transitions from Upsilon(4S) resonance with emission of eta meson and update of Upsilon(5S) - B-(*())(B) over bar*pi analysis from Belle.

On universal knot polynomials / Mkrtchyan,R, Mironov,A, Morozov,A / JOURNAL OF HIGH ENERGY PHYSICS. - 2016.

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We present a universal knot polynomials for 2- and 3-strand torus knots in adjoint representation, by universalization of appropriate Rosso-Jones formula. According to universality, these polynomials coincide with adjoined colored HOMFLY and Kauffman polynomials at SL and SO/Sp lines on Vogel's plane, respectively and give their exceptional group's counterparts on exceptional line. We demonstrate that [m,n]=[n,m] topological invariance, when applicable, take place on the entire Vogel's plane. We also suggest the universal form of invariant of figure eight knot in adjoint representation, and suggest existence of such universalization for any knot in adjoint and its descendant representations. Properties of universal polynomials and applications of these results are discussed.

Modeling of low-energy charged particles passage through GAMMA-400 gamma-telescope thermal insulation and two-layer plastic scintillation detectors used as anticoincidence shield / Chasovikov,EN / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

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The results of low-energy charged particles passage through GAMMA-400 gamma-telescope thermal insulation and two-layer plastic scintillation detectors used as anticoincidence shield are presented. An existing GEANT4 GAMMA-400 model is used. Effects of thermal insulation on charged particle passage are investigated. These results will be used to testing the effect of low-energy charged particles flux on GAMMA-400 gamma-quanta registration capabilities. Sufficiently large energy deposition in two-layer plastic anticoincidence scintillation detectors might interfere with high-energy particle registration and identification. However, GAMMA-400 detection capabilities are not affected by this, as the energy deposition in the lower layer of S3 is less than 1.5 MeV in all simulated cases. This value is less than threshold for high energy particles identification start (2.5 MeV). It makes impossible to incorrectly identify a low-energy charged particle energy deposition as backsplash from a high-energy gamma-quantum.

Modifying a cylindrical surface irradiated with a radial beam of argon ions with energies of up to 5 keV / Kalin,B.A./ Bulletin of the Russian Academy of Sciences: Physics. - 2016.

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Aspects of the ion modification of the outer surfaces of tubular samples of E110 (Zr–1% Nb) alloy is studied. The samples are irradiated with a radial beam of argon ions (0.5–5.0 keV, (5–10) × 10sup18/sup ion/cmsup2/sup) on the ILUR-03 setup. It is found that such ion bombardment smooths the relief formed by mechanical abrasive treatment. It is demonstrated that the effect of ion polishing is most pronounced for surface irregularities of a certain size. © 2016, Allerton Press, Inc.

Monitoring of sup235/supU content of fuel assemblies for nuclear reactors based on neutron and γ-ray scintillation detector systems / Dubenkov,N.E. / Instruments and Experimental Techniques. - 2016.

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A model of the setup for determining the sup235/supU content of a fuel assembly for WWER-440 reactors is described. The setup operates based on the digital technology for discriminating neutron and photon scintillation responses. An AmLi source is used as an external neutron source. A three-channel system for detecting fission particle coincidences is based on EJ-309 scintillators. A set of digital codes for obtaining and analyzing neutron-neutron (nn), neutron-γ (nγ), and γ-γ (γγ) coincidences has been developed. Dependences of double coincidences have been experimentally obtained and analyzed with the aim of determining the sup235/supU content of the fuel assembly. It is shown that fission neutrons and coincidences of the nn and nn + γn + nγ types are the best informative parameters for the sup235/supU content of the fuel assembly. © 2016, Pleiades Publishing, Inc.

Decomposing Nekrasov decomposition / Morozov,A., Zenkevich,Y. / Journal of High Energy Physics. - 2016.

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Abstract: AGT relations imply that the four-point conformal block admits a decomposition into a sum over pairs of Young diagrams of essentially rational Nekrasov functions — this is immediately seen when conformal block is represented in the form of a matrix model. However, the q-deformation of the same block has a deeper decomposition — into a sum over a quadruple of Young diagrams of a product of four topological vertices. We analyze the interplay between these two decompositions, their properties and their generalization to multi-point conformal blocks. In the latter case we explain how Dotsenko-Fateev all-with-all (star) pair “interaction” is reduced to the quiver model nearest-neighbor (chain) one. We give new identities for q-Selberg averages of pairs of generalized Macdonald polynomials. We also translate the slicing invariance of refined topological strings into the language of conformal blocks and interpret it as abelianization of generalized Macdonald polynomials. © 2016, The Author(s).

Are there p-adic knot invariants? / Morozov,A.Y. / Theoretical and Mathematical Physics(Russian Federation). - 2016.

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We suggest using the Hall–Littlewood version of the Rosso–Jones formula to define the germs of p-adic HOMFLY-PT polynomials for torus knots [m, n] as coefficients of superpolynomials in a q-expansion. In this form, they have at least the [m, n] ↔ [n, m] topological invariance. This opens a new possibility to interpret superpolynomials as p-adic deformations of HOMFLY polynomials and poses a question of generalizing to other knot families, which is a substantial problem for several branches of modern theory. © 2016, Pleiades Publishing, Ltd.

MR Imaging Biomarkers in Oncology Clinical Trials / Abramson,RichardG / MAGNETIC RESONANCE IMAGING CLINICS OF NORTH AMERICA. - 2016.

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The authors discuss eight areas of quantitative MR imaging that are currently used (RECIST, DCE-MR imaging, DSC-MR imaging, diffusion MR imaging) in clinical trials or emerging (CEST, elastography, hyperpolarized MR imaging, multiparameter MR imaging) as promising techniques in diagnosing cancer and assessing or predicting response of cancer to therapy. Illustrative applications of the techniques in the clinical setting are summarized before describing the current limitations of the methods.

Multi-strange baryon production in pPb collisions at sNN=5.02 TeV / Adam,J. / Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 2016.

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The multi-strange baryon yields in PbPb collisions have been shown to exhibit an enhancement relative to pp reactions. In this work, Ξ and Ω production rates have been measured with the ALICE experiment as a function of transverse momentum, pT, in pPb collisions at a centre-of-mass energy of sNN=5.02 TeV. The results cover the kinematic ranges 0.6 GeV/c<pT<7.2 GeV/c and 0.8 GeV/c<pT<5 GeV/c, for Ξ and Ω respectively, in the common rapidity interval -0.5<yCMS<0. Multi-strange baryons have been identified by reconstructing their weak decays into charged particles. The pT spectra are analysed as a function of event charged-particle multiplicity, which in pPb collisions ranges over one order of magnitude and lies between those observed in pp and PbPb collisions. The measured pT distributions are compared to the expectations from a Blast-Wave model. The parameters which describe the production of lighter hadron species also describe the hyperon spectra in high multiplicity pPb collisions. The yield of hyperons relative to charged pions is studied and compared with results from pp and PbPb collisions. A continuous increase in the yield ratios as a function of multiplicity is observed in pPb data, the values of which range from those measured in minimum bias pp to the ones in PbPb collisions. A statistical model qualitatively describes this multiplicity dependence using a canonical suppression mechanism, in which the small volume causes a relative reduction of hadron production dependent on the strangeness content of the hyperon. © 2016 The Author(s).

Multipion Bose-Einstein correlations in pp, p-Pb, and Pb-Pb collisions at energies available at the CERN Large Hadron Collider / Adam,J / PHYSICAL REVIEW C. - 2016.

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Three- and four-pionBose-Einstein correlations are presented in pp, p-Pb, and Pb-Pb collisions at the LHC. We compare our measured four-pion correlations to the expectation derived from two-and three-pion measurements. Such a comparison provides a method to search for coherent pion emission. We also present mixed-charge correlations in order to demonstrate the effectiveness of several analysis procedures such as Coulomb corrections. Same-charge four-pion correlations in pp and p-Pb appear consistent with the expectations from three-pion measurements. However, the presence of non-negligible background correlations in both systems prevent a conclusive statement. In Pb-Pb collisions, we observe a significant suppression of three-and four-pion Bose-Einstein correlations compared to expectations from two-pionmeasurements. There appears to be no centrality dependence of the suppression within the 0%-50% centrality interval. The origin of the suppression is not clear. However, by postulating either coherent pion emission or large multibody Coulomb effects, the suppression may be explained.

Multiplicity and transverse momentum evolution of charge-dependent correlations in pp, p-Pb, and Pb-Pb collisions at the LHC / Adam,J / EUROPEAN PHYSICAL JOURNAL C. - 2016.

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We report on two-particle charge-dependent correlations in pp, p-Pb, and Pb-Pb collisions as a function of the pseudorapidity and azimuthal angle difference, Delta eta and Delta phi respectively. These correlations are studied using the balance function that probes the charge creation time and the development of collectivity in the produced system. The dependence of the balance function on the event multiplicity as well as on the trigger and associated particle transversemomentum (p(T)) in pp, p-Pb, and Pb-Pb collisions at root s(NN) = 7, 5.02, and 2.76 TeV, respectively, are presented. In the low transverse momentum region, for 0.2 p(T) 2.0 GeV/c, the balance function becomes narrower in both Delta eta and Delta phi directions in all three systems for events with higher multiplicity. The experimental findings favor models that either incorporate some collective behavior (e.g. AMPT) or different mechanisms that lead to effects that resemble collective behavior (e.g. PYTHIA8 with color reconnection). For higher values of transverse momenta the balance function becomes even narrower but exhibits no multiplicity dependence, indicating that the observed narrowing with increasing multiplicity at low pT is a feature of bulk particle production.

Muon reconstruction performance of the ATLAS detector in proton-proton collision data at root s=13 TeV / Aad,G / EUROPEAN PHYSICAL JOURNAL C. - 2016.

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This article documents the performance of the ATLAS muon identification and reconstruction using the LHC dataset recorded at root s = 13 TeVin 2015. Using a large sample of J/.psi - mu mu and Z - mu mu decays from 3.2 fb(-1) of pp collision data, measurements of the reconstruction efficiency, as well as of the momentum scale and resolution, are presented and compared to Monte Carlo simulations. The reconstruction efficiency is measured to be close to 99 % over most of the covered phase space (vertical bar eta vertical bar 2.5 and 5 p(T) 100 GeV). The isolation efficiency varies between 93 and 100 % depending on the selection applied and on the momentum of the muon. Both efficiencies are well reproduced in simulation. In the central region of the detector, the momentum resolution is measured to be 1.7 % (2.3 %) for muons from J/psi - mu mu(Z - mu mu) decays, and the momentum scale is known with an uncertainty of 0.05 %. In the region vertical bar eta vertical bar 2.2, the p(T) resolution for muons from Z - mu decays is 2.9 % while the precision of the momentum scale for low-p(T) muons from J/psi - mu mu decays is about 0.2 %.

Natural and Industrial Background Irradiation Doses for the General Public / Tsov’yanov,A.G. / Atomic Energy. - 2016.

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This article contains information on the content of radionuclides in air in the sanitary-hygienic and observation zones of objects, in open-reservoir water located in the sanitary-hygienic and observation zones, and in locally produced food products. Data are presented on the most representative radiation exposure for the general public under normal operating conditions of industrial sources as well as on the radiation conditions and radiation exposure for the public in 2013 on territory within the jurisdiction of the Federal Medical-Biological Agency of Russia. © 2016 Springer Science+Business Media New York

Near-barrier neutron transfer in reactions with 3He nucleus / Naumenko,M.A. / Bulletin of the Russian Academy of Sciences: Physics. - 2016.

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Experimental cross sections for the formation of 196,198Au isotopes in the 3He + 197Au reaction and 44,46Sc isotopes in the 3He + 45Sc reaction are analyzed. To calculate transfer probabilities and cross sections, the time-dependent Schrödinger equation is numerically solved for the external neutrons of the 3He, 45Sc, and 197Au nuclei. It is shown that the contribution from the fusion channel with subsequent evaporation is important for the 3He + 45Sc reaction and negligibly small for the 3He + 197Au reaction. Fusion–evaporation is taken into account using the NRV and PACE codes. Calculation results demonstrate overall satisfactory agreement with experimental data. © 2016, Allerton Press, Inc.

Galactic and extragalactic contributions to the astrophysical muon neutrino signal / Neronov,Andrii, Semikoz,Dmitry / PHYSICAL REVIEW D. - 2016.

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In a previous study, we have shown that spectral and anisotropy properties of IceCube astrophysical neutrino signals reveal evidence for a sizeable Galactic contribution to the neutrino flux in the Southern Hemisphere. We check if the Galactic contribution is detectable in the astrophysical muon neutrino flux observed from a low positive declinations region of the Northern sky. Estimating the Galactic neutrino flux in this part of the sky from gamma-ray and Southern sky neutrino data, we find that the Northern sky astrophysical muon neutrino signal shows an excess over the Galactic flux. This points to the presence of an additional hard spectrum (extragalactic or large-scale Galactic halo) component of the astrophysical neutrino flux. We show that the Galactic flux component should still be detectable in the muon neutrino data in a decade-long IceCube exposure.

Recent results of the femtoscopic measurements from RHIC and LHC / Nigmatkulov,GA / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

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The two-particle correlations at low relative momenta (correlation femtoscopy) are sensitive to quantum statistics and allow to measure the space-time picture of the system evolution created in heavy-ion (HI) and particle collisions. The spatio-temporal parameters extracted from HI collisions describe the system at the last moment of the collision evolution kinetic freeze-out and provide the essential information about the formation of the quark-gluon plasma. The measurements at many facilities showed the dependencies of the spacial scales from the event multiplicity and particle transverse mass,mT. In this paper we show recent results obtained at RHIC and LHC energies and compare them to the theoretical expectations.

Bose-Einstein correlations of charged kaons in p plus p collisions with the STAR detector / Nigmatkulov,Grigory / 15TH INTERNATIONAL CONFERENCE ON STRANGENESS IN QUARK MATTER (SQM2015). - 2016.

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We report the results of charged kaon Bose Einstein Correlations (BEC) measured in proton proton collisions at root s =200 and 510 GeV with the STAR detector at Relativistic Heavy Ion Collider (RHIC). The one-dimensional correlation functions are studied as a function of the charged particle multiplicity. The femtoscopic radii, R, and the correlation strength, A, are extracted. The dependence of the source radii and the correlation strengths on the particle multiplicity are investigated.

CPT breaking and electric charge non-conservation / Novikov,VA / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

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We demonstrate that CPT-violation due to the e(+)e(-) mass difference breaks an electric current conservation and generates a photon mass. Cosmological bounds on the photon mass lead to the bound for e(+)e(-) mass difference that is 10-15 orders of magnitude stronger than any direct experimental bounds.

Observation of delayed electron emission in a two-phase liquid xenon detector / Karelin,A.K. / Journal of Instrumentation. - 2016.

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Results of the experimental study of electron emission from liquid xenon via electroluminescence of the gas phase are presented. We report on observation of a peculiar kind of delayed electroluminescent signal following initial electroluminescence caused by ionizing particles. We also present the results of a study of spontaneous single electron emission following cosmic muon signals. It was found that the rate of spontaneous single electron signals strongly depends on the time passed since the initial electroluminescence happened. The analysis of experimental data showed that both spontaneous single electron signals and delayed electroluminescent signals are associated with ionization electrons which are trapped by the potential barrier at the interface. © 2016 IOP Publishing Ltd and Sissa Medialab srl.

Observation of Long-Range Elliptic Azimuthal Anisotropies in root s=13 and 2.76 TeV pp Collisions with the ATLAS Detector / Aad,G / PHYSICAL REVIEW LETTERS. - 2016.

Annotation:

ATLAS has measured two-particle correlations as a function of the relative azimuthal angle, Delta phi, and pseudorapidity, Delta eta, in root s = 13 and 2.76 TeV pp collisions at the LHC using charged particles measured in the pseudorapidity interval vertical bar eta vertical bar 2.5. The correlation functions evaluated in different intervals of measured charged-particle multiplicity show a multiplicity-dependent enhancement at Delta phi similar to 0 that extends over a wide range of Delta eta, which has been referred to as the "ridge." Per-trigger-particle yields, Y(Delta phi) are measured over 2 vertical bar Delta eta vertical bar 5. For both collision energies, the Y(Delta phi) distribution in all multiplicity intervals is found to be consistent with a linear combination of the per-trigger-particle yields measured in collisions with less than 2 phi reconstructed tracks, and a constant combinatoric contribution modulated by cos (2 Delta phi). The fitted Fourier coefficient, nu(2,2), exhibits factorization, suggesting that the ridge results from per-event cos (2 phi) modulation of the single-particle distribution with Fourier coefficients nu(2). The nu(2) values are presented as a function of multiplicity and transverse momentum. They are found to be approximately constant as a function of multiplicity and to have a p(T) dependence similar to that measured in p + Pb and Pb + Pb collisions. The nu(2) values in the 13 and 2.76 TeV data are consistent within uncertainties. These results suggest that the ridge in pp collisions arises from the same or similar underlying physics as observed in p + Pb collisions, and that the dynamics responsible for the ridge has no strong root s dependence.

Observation of the Decay Bs0 →k0 K 0 / Pal,B. / Physical Review Letters. - 2016.

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We measure the decay Bs0→K0K0 using data collected at the ?(5S) resonance with the Belle detector at the KEKB e+e- collider. The data sample used corresponds to an integrated luminosity of 121.4 fb-1. We measure a branching fraction B(Bs0→K0K0)=[19.6-5.1+5.8(stat)±1.0(syst)±2.0(NBs0Bs0)]×10-6 with a significance of 5.1 standard deviations. This measurement constitutes the first observation of this decay. © 2016 American Physical Society.

Observation of top quark pairs produced in association with a vector boson in pp collisions at root s=8 TeV / Khachatryan,V / JOURNAL OF HIGH ENERGY PHYSICS. - 2016.

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Measurements of the cross sections for top quark pairs produced in association with a W or Z boson are presented, using 8 TeV pp collision data corresponding to an integrated luminosity of 19.5 fb(-1), collected by the CMS experiment at the LHC. Final states are selected in which the associated W boson decays to a charged lepton and a neutrino or the Z boson decays to two charged leptons. Signal events are identified by matching reconstructed objects in the detector to specific final state particles from t (t) over barW or t (t) over barZ decays. The t (t) over barW cross section is measured to be 382(-102)(+117) fb with a significance of 4.8 standard deviations from the background-only hypothesis. The t (t) over barZ cross section is measured to be 242(-55)(+65) fb with a significance of 6.4 standard deviations from the background-only hypothesis. These measurements are used to set bounds on five anomalous dimension-six operators that would affect the t (t) over barW and t (t) over barZ cross sections.

Observation of Zb (10610) and Zb (10650) Decaying to B Mesons / Garmash,A. / Physical Review Letters. - 2016.

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We report the analysis of the three-body e+e-→BBπ±, BB∗π±, and B∗B∗π± processes, including the first observations of the Zb±(10610)→[BB∗+c.c.]± and Zb±(10650)→[B∗B∗]± transitions that are found to dominate the corresponding final states. We measure Born cross sections for the three-body production of σ(e+e-→[BB∗+c.c.]±π)=[17.4±1.6(stat)±1.9(syst)] pb and σ(e+e-→[B∗B∗]±π)=[8.75±1.15(stat)±1.04(syst)] pb and set a 90% C.L. upper limit of σ(e+e-→[BB]±π)2.9 pb. The results are based on a 121.4 fb-1 data sample collected with the Belle detector at a center-of-mass energy near the (10860) peak. © 2016 American Physical Society.

On a possible solution to gamma-ray overabundance arising in dark matter explanation of cosmic antiparticle excess / Alekseev,VV / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

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As we are going to show, some self-interacting dark matter models may provide an intriguing solution to the "cosmic antiparticle excess vs. isotropic diffuse gamma-ray background" problem (an overproduction of diffuse gamma rays, arising in any reasonable decaying or annihilating dark matter model explaining high-energy charged cosmic antiparticles anomalous abundance).

On physical and numerical instabilities arising in simulations of non-stationary radiatively cooling shocks / Badjin,D.A. / Monthly Notices of the Royal Astronomical Society. - 2016.

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We describe our modelling of the radiatively cooling shocks and their thin shells with various numerical tools in different physical and calculational setups.We inspect structure of the dense shell, its formation and evolution, pointing out physical and numerical factors that sustain its shape and also may lead to instabilities.We have found that under certain physical conditions, the circular shaped shells show a strong bending instability and successive fragmentation on Cartesian grids soon after their formation, while remain almost unperturbed when simulated on polar meshes. We explain this by physical Rayleigh-Taylor-like instabilities triggered by corrugation of the dense shell surfaces by numerical noise. Conditions for these instabilities follow from both the shell structure itself and from episodes of transient acceleration during re-establishing of dynamical pressure balance after sudden radiative cooling onset. They are also easily excited by physical perturbations of the ambient medium. The widely mentioned non-linear thin shell instability, in contrast, in tests with physical perturbations is shown to have only limited chances to develop in real radiative shocks, as it seems to require a special spatial arrangement of fluctuations to be excited efficiently. The described phenomena also set new requirements on further simulations of the radiatively cooling shocks in order to be physically correct and free of numerical artefacts. © 2016 The Authors.

Optical and structural properties of Cusub2/subZnSnSsub4/sub thin films obtained by pulsed laser deposition in a Hsub2/subS atmosphere with subsequent annealing in a Nsub2/sub atmosphere / Teterina,G.D. / Semiconductors. - 2016.

Annotation:

The structural and optical properties of Cu2ZnSnS4 thin-film layers formed by reactive pulsed laser deposition in a H2S atmosphere at room temperature with the use of a Cu metal target and a Zn–Sn alloy target are studied in relation to the parameters of annealing in a N2 atmosphere. © 2016, Pleiades Publishing, Ltd.

OPTIMIZATION OF ELECTRIC-PULSE CONSOLIDATION REGIMES TO OBTAIN HIGH-DENSITY DISPERSION-HARDENED REACTOR STEEL / Nikitina,AA / ATOMIC ENERGY. - 2016.

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Research on the development of EP-450 high-density, Y2O3-oxide dispersion-hardened, reactor ferrite-martensite steel is described. All available parameters influencing the final density of the compacts were varied in the course of the preparation of the powders and electric-pulse consolidation. The research established that samples with density equal to 99% of the theoretical value can be obtained for the following optimized mechanical activation and electric-pulse consolidation parameters: mechanical alloying time 30 h, optimal Y2O3 amount 0.2-0.5 wt.%, sintering temperature 825-890 degrees C, climb rate to the prescribed temperature 300 degrees C/min, load 70-80 MPa, holding time at the load - without isothermal holding or holding for = 3 min.

Optimization of the light yield properties from scintillator tiles read out directly by silicon photomultipliers / Bobchenko,B / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

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The research of the light yield from the scintillator tiles with direct readout by silicon photomultipliers (SiPM) has been performed. The tile size is 30 x 30 x 3 mm(3) as planned for the AHCAL of the ILD at the ILC. The different tile geometries were studied. The uniformity of light yield has been optimized and one geometry has been selected. The results are compared to the studies on the same topic, performed by another groups.

The inverse beta decay: a study of cross section / Oralbaev,A, Titov,O, Skorokhvatov,M / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

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Knowledge of antineutrino interaction cross-sections is an important and necessary ingredient in many measurements. With the advent of new precision experiments, the demands on better understanding of neutrino interactions is becoming even greater. The purpose of this report is to survey our current knowledge of the inverse beta decay cross-sections and to do a comparison the theoretical analysis with experimental data.

Overview and accomplishments of the Borexino experiment / Ranucci,G / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

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The Borexino experiment is running at the Laboratori del Gran Sasso in Italy since 2007. Its technical distinctive feature is the unprecedented ultralow background of the inner scintillating core, which is the basis of the outstanding achievements accumulated by the experiment. In this talk, after recalling the main features of the detector, the impressive solar data gathered so far by the experiment will be summarized, with special emphasis to the most recent and prominent result concerning the detection of the fundamental pp solar neutrino flux, which is the direct probe of the engine mechanism powering our star. Such a milestone measurement puts Borexino in the unique situation of being the only experiment able to do solar neutrino spectroscopy over the entire solar spectrum; the counterpart of this peculiar status in the oscillation interpretation of the data is the capability of Borexino alone to perform the full validation across the solar energy range of the MSW-LMA paradigm. The talk will be concluded highlighting the perspectives for the final stage of the solar program of the experiment, centered on the goal to fully complete the solar spectroscopy with the missing piece of the CNO neutrinos. If successful, such a measurement would represent the final crowning of the long quest of Borexino to unravel all the properties of the neutrinos from the Sun.

Flavor physics at Super B-factories era / Pakhlov,P, Uglov,T / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

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We review numerous results from the B-Factories, obtained last decade. They provide currently strong constraints on New Physics extensions beyond the Standard Model. We discuss the physics program at Super B-factory, a next generation asymmetric collider with the luminosity almost two orders of magnitude higher than those achieved at the existing colliders, and its capability in cooperation with LHC of new insights into New Physics phenomena.

The charged Z(c) states from rescattering in conventional B decays / Pakhlov,P, Uglov,T / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

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In this paper we discuss a possible interpretation of the charged charmonium-like states observed in B decays as a rescattering effect. This approach allows to avoid introduction of exotic hadrons into the theory, while explains the unusual peaking structures 4observed recently in three body B decays. In particular, the peaks in the psi(2S)pi(+) mass spectrum are ascribed to the rescattering process with kinematics governed by the presence of conventional radial excitations, the D-s(()*()') resonances, in the hidden intermediate state. Our predictions are compared to the LHCb results.

PAMELA's measurements of geomagnetic cutoff variations during the 14 December 2006 storm / Adriani,O. / Space Weather. - 2016.

Annotation:

Data from the Payload for Antimatter Matter Exploration and Light-nuclei Astrophysics (PAMELA) satellite experiment were used to measure the geomagnetic cutoff for high-energy (≳ 80MeV) protons during the 14 December 2006 geomagnetic storm. The variations of the cutoff latitude as a function of rigidity were studied on relatively short timescales, corresponding to spacecraft orbital periods (∼94 min). Estimated cutoff values were compared with those obtained by means of a trajectory-tracing approach based on a dynamical empirical modeling of the Earth's magnetosphere. We found significant variations in the cutoff latitude, with a maximum suppression of ∼7° at lowest rigidities during the main phase of the storm. The observed reduction in the geomagnetic shielding and its temporal evolution were related to the changes in the magnetospheric configuration, investigating the role of interplanetary magnetic field, solar wind, and geomagnetic parameters. PAMELA's results represent the first direct measurement of geomagnetic cutoffs for protons with kinetic energies in the sub-GeV and GeV region. ©2016. American Geophysical Union.

Particle identification in ALICE: a Bayesian approach / Adam,J / EUROPEAN PHYSICAL JOURNAL PLUS. - 2016.

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We present a Bayesian approach to particle identification (PID) within the ALICE experiment. The aim is to more effectively combine the particle identification capabilities of its various detectors. After a brief explanation of the adopted methodology and formalism, the performance of the Bayesian PID approach for charged pions, kaons and protons in the central barrel of ALICE is studied. PID is performed via measurements of specific energy loss (dE/dx) and time of flight. PID efficiencies and misidentification probabilities are extracted and compared with Monte Carlo simulations using high-purity samples of identified particles in the decay channels K-S(0) - pi(-)pi(+), phi - K-K+, and A - p pi(-) in p-Pb collisions at root sNN = 5.02 TeV. In order to thoroughly assess the validity of the Bayesian approach, this methodology was used to obtain corrected p(T) spectra of pions, kaons, protons, and D-0 mesons in pp collisions at root s = 7TeV. In all cases, the results using Bayesian PID were found to be consistent with previous measurements performed by ALICE using a standard PID approach. For the measurement of D-0 - K-pi(+), it was found that a Bayesian PID approach gave a higher signal-to-background ratio and a similar or larger statistical significance when compared with standard PID selections, despite a reduced identification efficiency. Finally, we present an exploratory study of the measurement of A(c)(+) - pK(-)pi(+) in pp collisions at root s = 7TeV, using the Bayesian approach for the identification of its decay products.

Simulation of surface radiation defects leakage current SiPM using Synopsys TCAD / Parygin,PP, Popova,EV, Grachev,VM / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

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Synopsys TCAD is a professional software for the development of the semiconductor technological process and device simulaion. In order to study a radiation damage of the surface of silicon photomultipliers (SiPMs) the simulation of these devices using Synopsys TCAD has been made. Experimental samples were produced by KETEK GmbH and have been irradiated with the different doses of X-rays with an energy of E approximate to 12 keV. The current-voltage characteristics below breakdown measured before and after irradiations have been simulated with TCAD. Obtained curves for experimental and simulation data are presented.

Patient Radiation Dose During Radiological Examinations / Tsov’yanov,A.G. / Atomic Energy. - 2016.

Annotation:

This article contains information obtained in 2013 on the structure and number of radiological procedures by organ type and group and collective and average patient radiation dose on the territories within the jurisdiction of the Federal Medical-Biological Agency of Russia. © 2016 Springer Science+Business Media New York

Performance of b-jet identification in the ATLAS experiment / Aad,G. / Journal of Instrumentation. - 2016.

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The identification of jets containing b hadrons is important for the physics programme of the ATLAS experiment at the Large Hadron Collider. Several algorithms to identify jets containing b hadrons are described, ranging from those based on the reconstruction of an inclusive secondary vertex or the presence of tracks with large impact parameters to combined tagging algorithms making use of multi-variate discriminants. An independent b-tagging algorithm based on the reconstruction of muons inside jets as well as the b-tagging algorithm used in the online trigger are also presented. The b-jet tagging efficiency, the c-jet tagging efficiency and the mistag rate for light flavour jets in data have been measured with a number of complementary methods. The calibration results are presented as scale factors defined as the ratio of the efficiency (or mistag rate) in data to that in simulation. In the case of b jets, where more than one calibration method exists, the results from the various analyses have been combined taking into account the statistical correlation as well as the correlation of the sources of systematic uncertainty. © CERN 2016 for the benefit of the ATLAS collaboration, published under the terms of the Creative Commons Attribution 3.0 License by IOP Publishing Ltd and Sissa Medialab srl.

Performance of two Askaryan Radio Array stations and first results in the search for ultrahigh energy neutrinos / Allison,P. / Physical Review D - Particles, Fields, Gravitation and Cosmology. - 2016.

Annotation:

Ultrahigh energy neutrinos are interesting messenger particles since, if detected, they can transmit exclusive information about ultrahigh energy processes in the Universe. These particles, with energies above 1016 eV, interact very rarely. Therefore, detectors that instrument several gigatons of matter are needed to discover them. The ARA detector is currently being constructed at the South Pole. It is designed to use the Askaryan effect, the emission of radio waves from neutrino-induced cascades in the South Pole ice, to detect neutrino interactions at very high energies. With antennas distributed among 37 widely separated stations in the ice, such interactions can be observed in a volume of several hundred cubic kilometers. Currently three deep ARA stations are deployed in the ice, of which two have been taking data since the beginning of 2013. In this article, the ARA detector "as built" and calibrations are described. Data reduction methods used to distinguish the rare radio signals from overwhelming backgrounds of thermal and anthropogenic origin are presented. Using data from only two stations over a short exposure time of 10 months, a neutrino flux limit of 1.5×10-6 GeV/cm2/s/sr is calculated for a particle energy of 1018 eV, which offers promise for the full ARA detector. © 2016 American Physical Society.

Performance studies of the hodoscope prototype for the NA62 experiment / Duk,V. / Journal of Instrumentation. - 2016.

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A hodoscope prototype to detect charged particles in the NA62 experiment at CERN SPS has been installed within the experimental setup in 2014 and exposed to the beam during the data taking period. Efficiency and time resolution for hodoscope tiles are measured. The average signal amplitude (proportional to the light yield) is estimated from the efficiency curves. The results of the tests have lead to several improvements in the final design of the hodoscope. © 2016 IOP Publishing Ltd and Sissa Medialab srl.

Performances investigation and material selection of PMT magnetic shields for the space experiments with GRIS and PING-M instruments / Faradzhaev,RM / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

PMT performances significantly change under the influence of magnetic field. Even the relatively weak geomagnetic field, which typically value is about 0.5 gauss, has an appreciable effect. Gain variations of PMT with 76 mm photocathode diameter may reach 10-20 % depending on spatial orientation. Therefore, it is necessary to apply magnetic shields for PMT response stability enhancement. The performances investigation of magnetic shields made of steel, permalloy and amorphous metallic alloy ribbon for PMT with 51 and 76 mm photocathode diameters was carried out. Based on obtained data the choice of magnetic shield was made.

Perspectives of the GAMMA-400 space observatory for high-energy gamma rays and cosmic rays measurements / Topchiev,NP / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

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The GAMMA-400 gamma-ray telescope is intended to measure the fluxes of gamma-rays and cosmic-ray electrons and positrons in the energy range from 100 MeV to several TeV. Such measurements concern the following scientific tasks: investigation of point sources of gamma-rays, studies of the energy spectra of Galactic and extragalactic diffuse emission, studies of gamma-ray bursts and gamma-ray emission from the Sun, as well as high precision measurements of spectra of high-energy electrons and positrons. Also the GAMMA-400 instrument provides the possibility for protons and nuclei measurements up to knee. But the main goal for the GAMMA-400 mission is to perform a sensitive search for signatures of dark matter particles in high-energy gamma-ray emission. To fulfill these measurements the GAMMA-400 gamma-ray telescope possesses unique physical characteristics in comparison with previous and present experiments. The major advantage of the GAMMA-400 instrument is excellent angular and energy resolution for gamma-rays above 10 GeV. The GAMMA-400 experiment will be installed onboard of the Navigator space platform, manufactured by the NPO Lavochkin Association. The expected orbit will be a highly elliptical orbit (with apogee 300.000 km and perigee 500 km) with 7 days orbital period. An important profit of such an orbit is the fact that the full sky coverage will always be available for gamma ray astronomy.

Polarimeters for the SPASCHARM Experiment / Bukreeva,SI / PROCEEDINGS OF THE 21ST INTERNATIONAL SYMPOSIUM ON SPIN PHYSICS (SPIN2014). - 2016.

Annotation:

A beam channel of polarized protons and antiprotons produced from decays of Lambda- and anti-Lambda-hyperons for the SPASCHARM experiment is to be built at IHEP U-70 accelerator in Protvino, Russia. The methods for tagging and measuring polarization of the beam (anti) protons are discussed in this report. The fast on-line beam tagging exploits the correlations between polarization and kinematics of (anti) protons originated from (anti)Lambda-decays. In the intermediate focus of primary target, decay (anti) protons of different transverse polarizations are spatially dispersed transversely with respect to the beam axis. The tagging system, consisting of fast beam detectors with good spatial resolution, measures the momentum and trajectory of each beam particle, including its position at the intermediate focus, thus allowing instant (on-line) assignment of the transverse polarization value to each (anti) proton. This system is also extremely useful for the beam channel tuning. While being fast and convenient, the polarization tagging fully relies on computing of particle transportation in the beam channel. In order to verify the real beam polarization and operating of the tagging system and beam channel, the independent absolute beam polarimetry is to be used. It is based on measuring the spin asymmetries in elastic scattering of beam (anti) protons in Coulomb-Nuclear Interference (CNI) and diffractive kinematic regions. It is estimated that less than one week of data taking would allow measuring an absolute beam polarization at the statistical accuracy of similar to 4-5%.

On ambiguity in knot polynomials for virtual knots / Popolitov,A., Morozov,A., Morozov,A. / Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 2016.

Annotation:

We claim that HOMFLY polynomials for virtual knots, defined with the help of the matrix-model recursion relations, contain more parameters, than just the usual q and A=qsupN/sup. These parameters preserve topological invariance and do not show up in the case of ordinary (non-virtual) knots and links. They are most conveniently observed in the hypercube formalism: then they substitute q-dimensions of certain fat graphs, which are not constrained by recursion and can be chosen arbitrarily. The number of these new topological invariants seems to grow fast with the number of non-virtual crossings: 0, 1, 1, 5, 15, 91, 784, 9160, ... This number can be decreased by imposing the factorization requirement for composites, in addition to topological invariance - still freedom remains. None of these new parameters, however, appears in HOMFLY for Kishino unknot, which thus remains unseparated from the ordinary unknots even by this enriched set of knot invariants. © 2016 The Authors.

Premelting as studied by positron annihilation and emission Mossbauer spectroscopies / Byakov,V.M. / Journal of Physics: Conference Series. - 2016.

Annotation:

We have estimated a local heating which takes place owing to the ionization energy losses at the terminal part of a fast positron track and at nano-vicinities of the sup57/supFe Mössbauer nuclei in case of the emission Mössbauer spectroscopy. It is shown that in experiments close to the melting point one may expect local melting near the probe species. © Published under licence by IOP Publishing Ltd.

Probing lepton flavour violation via neutrinoless tau - 3 mu decays with the ATLAS detector / Aad,G / EUROPEAN PHYSICAL JOURNAL C. - 2016.

Annotation:

This article presents the sensitivity of the ATLAS experiment to the lepton-flavour-violating decays of tau - 3 mu. A method utilising the production of t leptons via W - tau nu decays is used. This method is applied to the sample of 20.3 fb(-1) of pp collision data at a centre-of-mass energy of 8 TeV collected by the ATLAS experiment at the LHC in 2012. No event is observed passing the selection criteria, and the observed (expected) upper limit on the tau lepton branching fraction into three muons, Br(tau - 3 mu), is 3.76 x 10(-7) (3.94 x 10(-7)) at 90 % confidence level.

Probing parton dynamics of QCD matter with Ω and φ production / Adamczyk,L. / Physical Review C - Nuclear Physics. - 2016.

Annotation:

We present measurements of Ω and φ production at midrapidity from Au+Au collisions at nucleon-nucleon center-of-mass energies sNN=7.7, 11.5, 19.6, 27, and 39 GeV by the STAR experiment at the BNL Relativistic Heavy Ion Collider (RHIC). Motivated by the coalescence formation mechanism for these strange hadrons, we study the ratios of N(Ω-+Ω¯+)/[2N(φ)]. These ratios as a function of transverse momentum pT fall on a consistent trend at high collision energies, but start to show deviations in peripheral collisions at sNN=19.6, 27, and 39 GeV, and in central collisions at 11.5 GeV in the intermediate pT region of 2.4-3.6 GeV/c. We further evaluate empirically the strange quark pT distributions at hadronization by studying the Ω/φ ratios scaled by the number of constituent quarks (NCQ). The NCQ-scaled Ω/φ ratios show a suppression of strange quark production in central collisions at 11.5 GeV compared to sNN≥19.6 GeV. The shapes of the presumably thermal strange quark distributions in 0-60% most central collisions at 7.7 GeV show significant deviations from those in 0-10% most central collisions at higher energies. These features suggest that there is likely a change of the underlying strange quark dynamics in the transition from quark matter to hadronic matter at collision energies below 19.6 GeV. © 2016 American Physical Society.

Production of light nuclei and anti-nuclei in pp and Pb-Pb collisions at energies available at the CERN Large Hadron Collider / Adam,J. / Physical Review C - Nuclear Physics. - 2016.

Annotation:

The production of (anti-)deuteron and (anti-)He3 nuclei in Pb-Pb collisions at sNN=2.76 TeV has been studied using the ALICE detector at the LHC. The spectra exhibit a significant hardening with increasing centrality. Combined blast-wave fits of several particles support the interpretation that this behavior is caused by an increase of radial flow. The integrated particle yields are discussed in the context of coalescence and thermal-statistical model expectations. The particle ratios, He3/d and He3/p, in Pb-Pb collisions are found to be in agreement with a common chemical freeze-out temperature of Tchem≈156 MeV. These ratios do not vary with centrality which is in agreement with the thermal-statistical model. In a coalescence approach, it excludes models in which nucleus production is proportional to the particle multiplicity and favors those in which it is proportional to the particle density instead. In addition, the observation of 31 anti-tritons in Pb-Pb collisions is reported. For comparison, the deuteron spectrum in pp collisions at s=7 TeV is also presented. While the p/π ratio is similar in pp and Pb-Pb collisions, the d/p ratio in pp collisions is found to be lower by a factor of 2.2 than in Pb-Pb collisions. © 2016 CERN. ©2016 CERN, for the ALICE Collaboration. Published by the American Physical Society under the terms of the Creative Commons Attribution 3.0 License. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.

Project of the URAN array for registration of atmospheric neutrons / Gromushkin,DM / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

The project of a new setup is directed at the registration of atmospheric neutrons (URAN) generated by hadronic component of extensive air showers (EAS). The setup includes 72 en-detector which simultaneously register two major EAS components: electromagnetic by the group passage of charged particles and hadron component by the thermal neutrons. The neutrons and charged particles are detected using a specialized scintillation composition made of granulated alloy of crystals based on the ZnS(Ag) powder with an admixture of B2O3.

Protactinium-231 as a new fissionable material for nuclear reactors that can produce nuclear fuel with stable neutron-multiplying properties / Shmelev,AN / KERNTECHNIK. - 2016.

Annotation:

Main purpose of the study is justifying doping of protactinium-231 into fuel compositions of advanced nuclear reactors with the ultimate aim to improve their operation safety and economic efficiency. Protactinium-231 could be generated in thorium blankets of hybrid thermonuclear facilities. The following results were obtained: 1. Protactinium-231 has some favorable features for its doping into nuclear fuel; 2. Protactinium containing fuel compositions can be characterized by the higher values of fuel burn-up, the longer values of fuel lifetime and the better proliferation resistance; 3. as protactinium-231 is the stronger neutron absorber than uranium-238, remarkably lower amounts of protactinium-231 may be doped into fuel compositions. The free space could be occupied by materials which are able to improve heat conductivity and refractoriness of fuel. As a consequence, operation safety of nuclear reactors could be upgraded.

Pseudorapidity and transverse-momentum distributions of charged particles in proton-proton collisions at √s = 13 TeV / Adam,J. / Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 2016.

Annotation:

The pseudorapidity (η) and transverse-momentum (pT) distributions of charged particles produced in proton-proton collisions are measured at the centre-of-mass energy √s=13 TeV. The pseudorapidity distribution in |η|<1.8 is reported for inelastic events and for events with at least one charged particle in |η|<1. The pseudorapidity density of charged particles produced in the pseudorapidity region |η|<0.5 is 5.31±0.18 and 6.46±0.19 for the two event classes, respectively. The transverse-momentum distribution of charged particles is measured in the range 0.15<pT<20 GeV/c and |η|<0.8 for events with at least one charged particle in |η| < 1. The evolution of the transverse momentum spectra of charged particles is also investigated as a function of event multiplicity. The results are compared with calculations from PYTHIA and EPOS Monte Carlo generators. © 2015 CERN for the benefit of the ALICE Collaboration.

Radiation hardness of semiconductor avalanche detectors for calorimeters in future HEP experiments / Mikhaylov,V / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

During the last years, semiconductor avalanche detectors are being widely used as the replacement of classical PMTs in calorimeters for many HEP experiments. In this report, basic selection criteria for replacement of PMTs by solid state devices and specific problems in the investigation of detectors radiation hardness are discussed. The design and performance of the hadron calorimeters developed for the future high energy nuclear physics experiments at FAIR, NICA, and CERN are discussed. The Projectile Spectator Detector (PSD) for the CBM experiment at the future FAIR facility, the Forward Calorimeter for the NA61 experiment at CERN and the Multi Purpose Detector at the future NICA facility are reviewed. Moreover, new methods of data analysis and results interpretation for radiation experiments are described. Specific problems of development of detectors control systems and possibilities of reliability improvement of multi-channel detectors systems are shortly overviewed. All experimental material is based on the investigation of SiPM and MPPC at the neutron source in NPI Rez.

RAPIDLY RISING TRANSIENTS from the SUBARU HYPER SUPRIME-CAM TRANSIENT SURVEY / Tanaka,M. / Astrophysical Journal. - 2016.

Annotation:

We present rapidly rising transients discovered by a high-cadence transient survey with the Subaru telescope and Hyper Suprime-Cam. We discovered five transients at z = 0.384-0.821, showing a rate of rise faster than 1 mag per day in the restframe near-ultraviolet wavelengths. The fast rate of rise and brightness are most similar to SN 2010aq and PS1-13arp, for which ultraviolet emission was detected within a few days after the shock breakout. The lower limit of the event rate of rapidly rising transients is ∼9% of core-collapse supernova rates, assuming the duration of rapid rise to be 1 day. We show that the light curves of the three faint objects agree with the cooling envelope emission from the explosion of red supergiants. The other two luminous objects, however, are brighter and faster than the cooling envelope emission. We interpret these two objects to be the shock breakout from a dense wind with a mass loss rate of ∼10sup-3/sup yrsup-1/sup, as also proposed for PS1-13arp. This mass loss rate is higher than that typically observed for red supergiants. The event rate of these luminous objects is 1% of the core-collapse supernova rate, and thus our study implies that more than ∼1% of massive stars can experience intense mass loss a few years before the explosion. © 2016. The American Astronomical Society. All rights reserved.

Rare earth elements materials production from apatite ores / Andrienko,O.S. / IOP Conference Series: Materials Science and Engineering. - 2016.

Annotation:

The paper deals with the study of processing apatite ores with nitric acid and extraction of the rare earth elements. The rare earth elements can be successfully separated and recovered by extraction from the nitrate- phosphate solution, being an tributyl phosphate as extraction agent. The developed scheme of the processing apatite concentrate provides obtaining rare earth concentrates with high qualitative characteristics. © Published under licence by IOP Publishing Ltd.

RBMK-1000 Computational-Measurement Diagnostics System / Morozov,A.Y. / Atomic Energy. - 2016.

Annotation:

Continuous monitoring and diagnostics of the core state make it possible to simultaneously analyze and adjust the operation of the nuclear reactor in the event of trouble. The ECRAN 3D system was developed for timely monitoring and diagnostics of the core state and the RBMK-1000 data base. This system makes it possible to discover failures and disruptions in the operation of the reactor xxx installation which are not recorded by the standard monitoring system. The failures could be associated with technical trouble as well as errors in entering the parameters of the reactor installation into the informational-measurement system. The algorithm of the ECRAN 3D system, the results of testing the system on real data on NPP, and the particularities of the interface are described. © 2016 Springer Science+Business Media New York

Recent applications of nuclear track emulsion / Mamatkulov,K.Z. / Mamatkulov, K.Z. - 2016.

Annotation:

Application of the nuclear track emulsion technique (NTE) in radioactivity and nuclear fission studies is discussed. It is suggested to use a HSP-1000 automated microscope for searching for a collinear cluster tri-partition of heavy nuclei implanted in NTE. Calibrations of α-particles and ion ranges in a novel NTE are carried out. Surface exposures of NTE samples to a Cf-252 source started. Planar events containing fragments and long-range α-particles as well as fragment triples only are studied. NTE samples are calibrated by ions Kr and Xe of energy of 1.2 and 3 A MeV. Use of the image recognition program "ImageJ" for obtaining characteristics of individual events and for events from the large scan area is presented. © Owned by the authors, published by EDP Sciences-SIF, 2016.

Recent results from Borexino and the first real time measure of solar pp neutrinos / Zavatarelli,S. / Nuclear and Particle Physics Proceedings. - 2016.

Annotation:

The Borexino detector was built starting from 1996 in the underground hall C of Gran Sasso National Laboratory (LNGS) in Italy under about 1400 m of rock (3800 m.w.e) and it is mostly aimed to the study in real-time of the low-energy solar neutrinos. Since the beginning of data taking, in May 2007, the unprecedented detector radio-purity made the performances of the detector unique: a milestone has been very recently achieved with the measurement of solar pp neutrino flux, providing the first direct observation in real time of the key fusion reaction powering the Sun. In this contribution the most important Borexino achievements to the fields of solar, geo-neutrino and particle physics are reviewed and the future perspectives discussed, emphasizing in particular the unique possibility of Borexino to cover at the end of its program the entire solar neutrino spectrum and to exploit the possible existence of a fourth sterile neutrino (SOX project). © 2015 Elsevier B.V.

Reconstruction and identification of tau lepton decays to hadrons and nu(tau) at CMS / Khachatryan,V / JOURNAL OF INSTRUMENTATION. - 2016.

Annotation:

This paper describes the algorithms used by the CMS experiment to reconstruct and identify tau - hadrons + nu(tau) decays during Run 1 of the LHC. The performance of the algorithms is studied in proton-proton collisions recorded at a centre-of-mass energy of 8 TeV, corresponding to an integrated luminosity of 19.7 fb(-1). The algorithms achieve an identification efficiency of 50-60%, with misidentification rates for quark and gluon jets, electrons, and muons between per mille and per cent levels.

Reconstruction of hadronic decay products of tau leptons with the ATLAS experiment / AtlasCollaboration,CERN / European Physical Journal C. - 2016.

Annotation:

This paper presents a new method of reconstructing the individual charged and neutral hadrons in tau decays with the ATLAS detector. The reconstructed hadrons are used to classify the decay mode and to calculate the visible four-momentum of reconstructed tau candidates, significantly improving the resolution with respect to the calibration in the existing tau reconstruction. The performance of the reconstruction algorithm is optimised and evaluated using simulation and validated using samples of Z→ ττ and Z(→ μμ) +jets events selected from proton–proton collisions at a centre-of-mass energy s=8TeV, corresponding to an integrated luminosity of 5 fb - 1. © 2016, The Author(s).

RED-100 detector for the first observation of the elastic coherent neutrino scattering off xenon nuclei / Akimov,DYu / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

The RED-100 (Russian Emission Detector) is being constructed for the experiment to search for elastic coherent neutrino scattering off atomic nuclei. This fundamental process was predicted several decades ago by the Standard Model of electroweak interactions but has not been discovered yet. The RED-100 is a two-phase emission xenon detector containing similar to 200 kg of the liquid Xe (similar to 100 kg of that is in a fiducial volume). One of the possible sites to carry out the experiment is the SNS (Spallation Neutron Source) facility at Oak Ridge National Laboratory, USA. SNS is the world's most intense pulsed source of neutrinos and unique place to study neutrino properties. The energy spectrum of neutrinos produced at the SNS extends up to similar to 50 MeV and satisfies coherence condition. These neutrinos give kinetic energies of Xe recoils up to a few tens of keV where the response of nuclear recoils is well-known from neutron calibrations of dark matter detectors. The detector will be deployed in the basement under the experimental hall at a distance of similar to 30 meters from the SNS target. The expected signal and background (neutron and gamma) are estimated for this specific location. The detector details, current status and future plans are provided.

Limits on Higgs boson couplings in Effective field theory / Reid,T, Belyaev,N / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

We review the Effective Field Theory (EFT) to make projections on physics beyond the Standard Model in the Higgs sector. We provide relations between the non-Standard Model couplings of the Strongly-Interacting Light Higgs (SILH) effective Lagrangian implemented in the eHDecay package and the corresponding terms of the spin-0 Higgs Characterisation model's effective Lagrangian used with the aMC@NLO Monte Carlo generator. Constraints on BSM couplings are determined on the basis of existing experimental limits on Higgs boson width and branching ratios.

Relating transverse structure of various parton distributions / Maji,Tanmay / JOURNAL OF HIGH ENERGY PHYSICS. - 2016

Annotation:

We present the results of T-even TMDs in a light front quark-diquark model of nucleons with the wave functions constructed from the soft-wall AdS/QCD prediction. The relations amongst TMDs are discussed. The pi dependence of the TMDs are compared with the t-dependence of the GPDs and the relation between the respective dependencies are found.

Repetitive patterns in rapid optical variations in the nearby black-hole binary V404 Cygni / Kimura,Mariko / NATURE. - 2016.

Annotation:

How black holes accrete surrounding matter is a fundamental yet unsolved question in astrophysics. It is generally believed that matter is absorbed into black holes via accretion disks, the state of which depends primarily on the mass-accretion rate. When this rate approaches the critical rate (the Eddington limit), thermal instability is supposed to occur in the inner disk, causing repetitive patterns of large-amplitude X-ray variability (oscillations) on timescales of minutes to hours(1). In fact, such oscillations have been observed only in sources with a high mass-accretion rate, such as GRS 1915+105 (refs 2, 3). These large-amplitude, relatively slow timescale, phenomena are thought to have physical origins distinct from those of X-ray or optical variations with small amplitudes and fast timescales (less than about 10 seconds) often observed in other black-hole binaries-for example, XTE J1118+480 (ref. 4) and GX 339-4 (ref. 5). Here we report an extensive multi-colour optical photometric data set of V404 Cygni, an X-ray transient source(6) containing a black hole of nine solar masses(7) (and a companion star) at a distance of 2.4 kiloparsecs (ref. 8). Our data show that optical oscillations on timescales of 100 seconds to 2.5 hours can occur at mass-accretion rates more than ten times lower than previously thought(1). This suggests that the accretion rate is not the critical parameter for inducing inner-disk instabilities. Instead, we propose that a long orbital period is a key condition for these large-amplitude oscillations, because the outer part of the large disk in binaries with long orbital periods will have surface densities too low to maintain sustained mass accretion to the inner part of the disk. The lack of sustained accretion-not the actual rate-would then be the critical factor causing large-amplitude oscillations in long-period systems.

Research of dysprosium, terbium and neodymium oxides fluoration / Sofronov,V. / Key Engineering Materials. - 2016.

Annotation:

Production of high energy permanent magnets (HEPM) on the basis of rare-earth metals is one of leading knowledge intensive branches of world industry. Raw materials for production of magnets are alloys. In order to increase HEPM magnetic features is used dysprosium and terbium additives. In a ladle fluoride technology of HEPM manufacturing on the basis of a system Nd-Fe-B, developed by authors, scientists implement the additives of dysprosium and terbium fluoride, by virtue where of there was conducted a research on fluoration kinetics of corresponding oxides by elemental fluorine. The present article quotes results of such research and defines main kinetic parameters of examined processes - diffusion coefficient, kinetic constant and activation energy. © Copyright 2016 Trans Tech Publications Ltd, Switzerland.

Results from the first use of low radioactivity argon in a dark matter search / Agnes,P. / Physical Review D - Particles, Fields, Gravitation and Cosmology. - 2016.

Annotation:

Liquid argon is a bright scintillator with potent particle identification properties, making it an attractive target for direct-detection dark matter searches. The DarkSide-50 dark matter search here reports the first WIMP search results obtained using a target of low-radioactivity argon. DarkSide-50 is a dark matter detector, using a two-phase liquid argon time projection chamber, located at the Laboratori Nazionali del Gran Sasso. The underground argon is shown to contain Ar39 at a level reduced by a factor (1.4±0.2)×103 relative to atmospheric argon. We report a background-free null result from (2616±43) kg d of data, accumulated over 70.9 live days. When combined with our previous search using an atmospheric argon, the 90% C.L. upper limit on the WIMP-nucleon spin-independent cross section, based on zero events found in the WIMP search regions, is 2.0×10-44 cm2 (8.6×10-44 cm2, 8.0×10-43 cm2) for a WIMP mass of 100 GeV/c2 (1 TeV/c2, 10 TeV/c2). © 2016 American Physical Society.

On black hole structures in scalar–tensor theories of gravity / Rodrigues,D.C., Bronnikov,K.A., Fabris,J.C. / International Journal of Modern Physics D. - 2016.

Annotation:

We review some properties of black hole structures appearing in gravity with a massless scalar field, with both minimal and nonminimal coupling. The main properties of the resulting cold black holes are described. The study of black holes in scalar-gravity systems is extended to (Formula presented.)-essence theories, and some examples are explicitly worked out. In these cases, even while the existence of horizons is possible, the metric regularity requirement on the horizon implies either a cold black type structure or a singular behavior of the scalar field. © 2016 World Scientific Publishing Company

On horizons and wormholes in k-essence theories / Rodrigues,D.C., Bronnikov,K.A., Fabris,J.C. / Gravitation and Cosmology. - 2016.

Annotation:

We study the properties of possible static, spherically symmetric configurations in k-essence theories with the Lagrangian functions of the form F(X), X ≡ ϕ,αϕ,supα/sup. A no-go theorem has been proved, claiming that a possible black-hole-like Killing horizon of finite radius cannot exist if the function F(X) is required to have a finite derivative dF/dX. Two exact solutions are obtained for special cases of kessence: one for F(X) = F0Xsup1/3/sup, another for F(X) = F0|X|sup1/2/sup − 2Λ, where F0 and Λ are constants. Both solutions contain horizons, are not asymptotically flat, and provide illustrations for the obtained nogo theorem. The first solution may be interpreted as describing a black hole in an asymptotically singular space-time, while in the second solution two horizons of infinite area are connected by a wormhole. © 2016, Pleiades Publishing, Ltd.

Kinetics of α’-phase nucleation during thermal aging of Fe–22% Cr alloy / Rogozhkin,S.V., Korchuganova,O.A., Aleev,A.A. / Inorganic Materials: Applied Research. - 2016.

Annotation:

The initial stage of phase separation of binary Fe–22 at % Cr alloy during thermal aging at 500°C is studied at the atomic-scale level by atom probe tomography. Upon the behavior analysis of pair-correlation function of chromium atoms, long-range correlations typical of spinodal decomposition are observed at short aging times, which disappear 25 h after aging. The analysis of 3D atomic maps shows that Cr-rich regions form at the initial steps of decomposition, where the chromium concentration increases with an increase in the aging time. At the aging time of ~100 h, the chromium concentration in the center of these regions reaches 80 at %, which corresponds to the α' phase. © 2016, Pleiades Publishing, Ltd.

Hierarchi problem / Rubin,SergeyG / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

The way to solve the hierarchy problem based on multidimensional gravity is discussed. Various metrics of deformed extra space are produced at the Planck scale. It is shown that the Higgs vacuum value depends on a metric of extra space and hence their different numerical values are realized in various universes. An interval of the Higgs vacuum values is proved include zero value. Our universe belongs to a set of universes the vacuum values of which are close to zero.

Dynamic intelligent systems integration and evolution of intelligent control systems architectures / Rybin,V.M., Rybina,G.V., Parondzhanov,S.S. / Advances in Intelligent Systems and Computing. - 2016.

Annotation:

The work deals with the problems of integration and hybridization in today’s dynamic intelligent systems. On the example of the individual classes of intelligent control systems (ICS) development experience the evolution of ICS architectures in accordance with the integration paradigm of artificial intelligence with models, methods and tools from other areas (automatic control system, simulation, etc.) are examined. An example of the integration of complex discrete systems simulation models with of dynamic integrated expert systems separate components developed in MEPhI and based on task-oriented methodology and tool set AT-TECHNOLOGY is described. © Springer International Publishing Switzerland 2016.

Search for a Higgs boson decaying into γ*γ→ℓℓγ with low dilepton mass in pp collisions at √s=8 TeV / Adam,J. / Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 2016.

Annotation:

A search is described for a Higgs boson decaying into two photons, one of which has an internal conversion to a muon or an electron pair (ℓℓγ). The analysis is performed using proton-proton collision data recorded with the CMS detector at the LHC at a centre-of-mass energy of 8 TeV, corresponding to an integrated luminosity of 19.7 fb-1. The events selected have an opposite-sign muon or electron pair and a high transverse momentum photon. No excess above background has been found in the three-body invariant mass range 120mℓℓγ150 GeV, and limits have been derived for the Higgs boson production cross section times branching fraction for the decay H→γ*γ→ℓℓγ, where the dilepton invariant mass is less than 20 GeV. For a Higgs boson with mH

Search for a high-mass Higgs boson decaying to a W boson pair in pp collisions at (Formula presented.) TeV with the ATLAS detector / TheATLAScollaboration / Journal of High Energy Physics. - 2016.

Annotation:

Abstract: A search for a high-mass Higgs boson H is performed in the H → WW → ℓνℓν and H → WW → ℓνqq decay channels using pp collision data corresponding to an integrated luminosity of 20.3 fbsup−1/sup collected at s=8(Formula presented.) TeV by the ATLAS detector at the Large Hadron Collider. No evidence of a high-mass Higgs boson is found. Limits on σH × BR(H → WW) as a function of the Higgs boson mass mH are determined in three different scenarios: one in which the heavy Higgs boson has a narrow width compared to the experimental resolution, one for a width increasing with the boson mass and modeled by the complex-pole scheme following the same behavior as in the Standard Model, and one for intermediate widths. The upper range of the search is mH = 1500 GeV for the narrow-width scenario and mH = 1000 GeV for the other two scenarios. The lower edge of the search range is 200–300 GeV and depends on the analysis channel and search scenario. For each signal interpretation, individual and combined limits from the two WW decay channels are presented. At mH = 1500 GeV, the highest-mass point tested, σH × BR(H → WW) for a narrow-width Higgs boson is constrained to be less than 22 fb and 6.6 fb at 95% CL for the gluon fusion and vector-boson fusion production modes, respectively.[Figure not available: see fulltext.] © 2016, The Author(s).

Search for a low-mass pseudoscalar Higgs boson produced in association with a bb[U+203E] pair in pp collisions at √s=8 TeV / Khachatryan,V. / Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 2016.

Annotation:

A search is reported for a light pseudoscalar Higgs boson decaying to a pair of τ leptons, produced in association with a bb pair, in the context of two-Higgs-doublet models. The results are based on pp collision data at a centre-of-mass energy of 8 TeV collected by the CMS experiment at the LHC and corresponding to an integrated luminosity of 19.7 fbsup-1/sup. Pseudoscalar boson masses between 25 and 80 GeV are probed. No evidence for a pseudoscalar boson is found and upper limits are set on the product of cross section and branching fraction to τ pairs between 7 and 39 pb at the 95% confidence level. This excludes pseudoscalar A bosons with masses between 25 and 80 GeV, with SM-like Higgs boson negative couplings to down-type fermions, produced in association with bb pairs, in Type II, two-Higgs-doublet models. © 2016 The Author(s).

Search for a massive resonance decaying into a Higgs boson and a W or Z boson in hadronic final states in proton-proton collisions at root s=8 TeV / Khachatryan,V / JOURNAL OF HIGH ENERGY PHYSICS. - 2016

Annotation:

A search for a massive resonance decaying into a standard-model-like Higgs boson (H) and a W or Z boson is reported. The analysis is performed on a data sample corresponding to an integrated luminosity of 19.7 fb(-1), collected in proton-proton collisions at a centre-of-mass energy of 8 TeV with the CMS detector at the LHC. Signal events, in which the decay products of Higgs, W, or Z bosons at high Lorentz boost are contained within single reconstructed jets, are identified using jet substructure techniques, including the tagging of b hadrons. This is the first search for heavy resonances decaying into HW or HZ resulting in an all-jet final state, as well as the first application of jet substructure techniques to identify H - WW* - 4q decays at high Lorentz boost. No significant signal is observed and limits are set at 95% confidence level on the production cross sections of W' and Z' in a model with mass-degenerate charged and neutral spin-1 resonances. Resonance masses are excluded for W' in the interval [1.0, 1.6] TeV, for Z' in the intervals [1.0, 1.1] and [1.3, 1.5] TeV, and for mass-degenerate W' and Z' in the interval [1.0, 1.7] TeV.

Search for a very light NMSSM Higgs boson produced in decays of the 125 GeV scalar boson and decaying into τ leptons in pp collisions at √s=8 TeV / TheCMScollaboration / Journal of High Energy Physics. - 2016.

Annotation:

A search for a very light Higgs boson decaying into a pair of τ leptons is presented within the framework of the next-to-minimal supersymmetric standard model. This search is based on a data set corresponding to an integrated luminosity of 19.7 fbsup−1/sup of proton-proton collisions collected by the CMS experiment at a centre-of-mass energy of 8 TeV. The signal is defined by the production of either of the two lightest scalars, h1 or h2, via gluon-gluon fusion and subsequent decay into a pair of the lightest Higgs bosons, a1 or h1. The h1 or h2 boson is identified with the observed state at a mass of 125 GeV. The analysis searches for decays of the a1 (h1) states into pairs of τ leptons and covers a mass range for the a1 (h1) boson of 4 to 8 GeV. The search reveals no significant excess in data above standard model background expectations, and an upper limit is set on the signal production cross section times branching fraction as a function of the a1 (h1) boson mass. The 95% confidence level limit ranges from 4.5 pb at ma1(mh1) = 8 GeV to 10.3 pb at ma1(mh1)=5 GeV. © 2016, The Author(s).

Search for an additional, heavy Higgs boson in the decay channel at in collision data with the ATLAS detector / Aad,G / EUROPEAN PHYSICAL JOURNAL C. - 2016.

Annotation:

A search is presented for a high-mass Higgs boson in the , , , and decay modes using the ATLAS detector at the CERN Large Hadron Collider. The search uses proton-proton collision data at a centre-of-mass energy of 8 TeV corresponding to an integrated luminosity of 20.3 fb. The results of the search are interpreted in the scenario of a heavy Higgs boson with a width that is small compared with the experimental mass resolution. The Higgs boson mass range considered extends up to for all four decay modes and down to as low as 140 , depending on the decay mode. No significant excess of events over the Standard Model prediction is found. A simultaneous fit to the four decay modes yields upper limits on the production cross-section of a heavy Higgs boson times the branching ratio to boson pairs. 95 % confidence level upper limits range from 0.53 pb at GeV to 0.008 pb at GeV for the gluon-fusion production mode and from 0.31 pb at GeV to 0.009 pb at GeV for the vector-boson-fusion production mode. The results are also interpreted in the context of Type-I and Type-II two-Higgs-doublet models.

Search for anomalous couplings in the W tb vertex from the measurement of double differential angular decay rates of single top quarks produced in the t-channel with the ATLAS detector / TheATLAScollaboration / Journal of High Energy Physics. - 2016.

Annotation:

Abstract: The electroweak production and subsequent decay of single top quarks is determined by the properties of the Wtb vertex. This vertex can be described by the complex parameters of an effective Lagrangian. An analysis of angular distributions of the decay products of single top quarks produced in the t -channel constrains these parameters simultaneously. The analysis described in this paper uses 4.6 fbsup−1/sup of proton-proton collision data at (Formula presented.) TeV collected with the ATLAS detector at the LHC. Two parameters are measured simultaneously in this analysis. The fraction f1 of decays containing transversely polarised W bosons is measured to be 0.37 ± 0.07 (stat.⊕syst.). The phase δ− between amplitudes for transversely and longitudinally polarised W bosons recoiling against left-handed b-quarks is measured to be −0.014π ± 0.036π (stat.⊕syst.). The correlation in the measurement of these parameters is 0.15. These values result in two-dimensional limits at the 95% confidence level on the ratio of the complex coupling parameters gR and VL, yielding Re[gR/VL] ∈ [−0.36, 0.10] and Im[gR/VL] ∈ [−0.17, 0.23] with a correlation of 0.11. The results are in good agreement with the predictions of the Standard Model.[Figure not available: see fulltext.] © 2016, The Author(s).

Search for anomalous single top quark production in association with a photon in pp collisions at √s = 8 TeV / TheCMScollaboration / Journal of High Energy Physics. - 2016.

Annotation:

The result of a search for flavor changing neutral currents (FCNC) through single top quark production in association with a photon is presented. The study is based on proton-proton collisions at a center-of-mass energy of 8 TeV using data collected with the CMS detector at the LHC, corresponding to an integrated luminosity of 19.8 fbsup−1/sup. The search for tγ events where t → Wb and W → μν is conducted in final states with a muon, a photon, at least one hadronic jet with at most one being consistent with originating from a bottom quark, and missing transverse momentum. No evidence of single top quark production in association with a photon through a FCNC is observed. Upper limits at the 95% confidence level are set on the tuγ and tcγ anomalous couplings and translated into upper limits on the branching fraction of the FCNC top quark decays: ℬ(t → uγ) < 1.3 × 10sup− 4/sup and ℬ(t → cγ) < 1.7 × 10sup− 3/sup. Upper limits are also set on the cross section of associated tγ production in a restricted phase-space region. These are the most stringent limits currently available. © 2016, The Author(s).

Search for B-0 - pi(-)tau(+)nu(tau) with hadronic tagging at Belle / Hamer,P / PHYSICAL REVIEW D. - 2016.

Annotation:

We search for the process B-0 - pi(-) tau(+)nu(tau) using the full Belle data set of 711 fb(-1), corresponding to 772 x 10(6)B (B) over bar pairs, collected at the gamma (4S) resonance with the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider. We reconstruct one B meson in a hadronic decay and search for the B-0 - pi(-)tau(+)nu(tau) process in the remainder of the event. No significant signal is observed and an upper limit of B(B-0 - pi(-) tau(+)nu(tau)) 2.5 x 10(-4) is obtained at the 90% confidence level.

Search for charged Higgs bosons in the Hsup±/sup → tb decay channel in pp collisions at √s = 8 TeV using the ATLAS detector / TheATLAScollaboration / Journal of High Energy Physics. - 2016.

Annotation:

Charged Higgs bosons heavier than the top quark and decaying via Hsup±/sup → tb are searched for in proton-proton collisions measured with the ATLAS experiment at (Formula presented.) TeV corresponding to an integrated luminosity of 20.3fbsup−1/sup. The production of a charged Higgs boson in association with a top quark, gb → tHsup±/sup, is explored in the mass range 200 to 600 GeV using multi-jet final states with one electron or muon. In order to separate the signal from the Standard Model background, analysis techniques combining several kinematic variables are employed. An excess of events above the background-only hypothesis is observed across a wide mass range, amounting to up to 2.4 standard deviations. Upper limits are set on the gb → tHsup±/sup production cross section times the branching fraction BR(Hsup±/sup → tb). Additionally, the complementary s-channel production, qqsup′/sup → Hsup±/sup, is investigated through a reinterpretation of Wsup′/sup → tb searches in ATLAS. Final states with one electron or muon are relevant for Hsup±/sup masses from 0.4 to 2.0 TeV, whereas the all-hadronic final state covers the range 1.5 to 3.0 TeV. In these search channels, no significant excesses from the predictions of the Standard Model are observed, and upper limits are placed on the qqsup′/sup → Hsup±/sup production cross section times the branching fraction BR(Hsup±/sup → tb). © 2016, The Author(s).

Search for charged Higgs bosons produced in association with a top quark and decaying via Hsup±/sup → τν using pp collision data recorded at s=13 TeV by the ATLAS detector / Jackson,P. / Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 2016.

Annotation:

Charged Higgs bosons produced in association with a single top quark and decaying via Hsup±/sup→τν are searched for with the ATLAS experiment at the LHC, using proton–proton collision data at s=13 TeV corresponding to an integrated luminosity of 3.2 fbsup−1/sup. The final state is characterised by the presence of a hadronic τ decay and missing transverse momentum, as well as a hadronically decaying top quark, resulting in the absence of high-transverse-momentum electrons and muons. The data are found to be consistent with the expected background from Standard Model processes. A statistical analysis leads to 95% confidence-level upper limits on the production cross section times branching fraction, σ(pp→[b]tHsup±/sup)×BR(Hsup±/sup→τν), between 1.9 pb and 15 fb, for charged Higgs boson masses ranging from 200 to 2000 GeV. The exclusion limits for this search surpass those obtained with the proton–proton collision data recorded at s=8 TeV. © 2016 The Author(s)

Search for dark matter and unparticles produced in association with a Z boson in proton-proton collisions at root s=8 TeV / Khachatryan,V / PHYSICAL REVIEW D. - 2016.

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A search for evidence of particle dark matter (DM) and unparticle production at the LHC has been performed using events containing two charged leptons, consistent with the decay of a Z boson, and large missing transverse momentum. This study is based on data collected with the CMS detector corresponding to an integrated luminosity of 19.7 fb(-1) of pp collisions at the LHC at a center-of-mass energy of 8 TeV. No significant excess of events is observed above the number expected from the standard model contributions. The results are interpreted in terms of 90% confidence level limits on the DM-nucleon scattering cross section, as a function of the DM particle mass, for both spin-dependent and spin-independent scenarios. Limits are set on the effective cutoff scale., and on the annihilation rate for DM particles, assuming that their branching fraction to quarks is 100%. Additionally, the most stringent 95% confidence level limits to date on the unparticle model parameters are obtained.

Search for dark matter produced in association with a Higgs boson decaying to two bottom quarks in pp collisions at s =8 TeV with the ATLAS detector / Aad,G. / Physical Review D - Particles, Fields, Gravitation and Cosmology. - 2016.

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This article reports on a search for dark matter pair production in association with a Higgs boson decaying to a pair of bottom quarks, using data from 20.3 fb-1 of pp collisions at a center-of-mass energy of 8 TeV collected by the ATLAS detector at the LHC. The decay of the Higgs boson is reconstructed as a high-momentum bb system with either a pair of small-radius jets, or a single large-radius jet with substructure. The observed data are found to be consistent with the expected Standard Model backgrounds. Model-independent upper limits are placed on the visible cross sections for events with a Higgs boson decaying into bb and large missing transverse momentum with thresholds ranging from 150 to 400 GeV. Results are interpreted using a simplified model with a Z′ gauge boson decaying into different Higgs bosons predicted in a two-Higgs-doublet model, of which the heavy pseudoscalar Higgs decays into a pair of dark matter particles. Exclusion limits are also presented for the mass scales of various effective field theory operators that describe the interaction between dark matter particles and the Higgs boson. © 2016 CERN, for the ATLAS Collaboration.

Search for direct top squark pair production in final states with two tau leptons in pp collisions at (Formula presented.)  TeV with the ATLAS detector / Aad,G. / European Physical Journal C. - 2016.

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A search for direct pair production of the supersymmetric partner of the top quark, decaying via a scalar tau to a nearly massless gravitino, has been performed using 20 fb (Formula presented.) of proton–proton collision data at (Formula presented.). The data were collected by the ATLAS experiment at the LHC in 2012. Top squark candidates are searched for in events with either two hadronically decaying tau leptons, one hadronically decaying tau and one light lepton, or two light leptons. No significant excess over the Standard Model expectation is found. Exclusion limits at (Formula presented.) confidence level are set as a function of the top squark and scalar tau masses. Depending on the scalar tau mass, ranging from the (Formula presented.) LEP limit to the top squark mass, lower limits between 490 and (Formula presented.) are placed on the top squark mass within the model considered. © 2016, CERN for the benefit of the ATLAS collaboration.

Search for excited leptons in proton-proton collisions at √s = 8 TeV / TheCMScollaboration / Journal of High Energy Physics. - 2016.

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A search for compositeness of electrons and muons is presented using a data sample of proton-proton collisions at a center-of-mass energy of (Formula presented.) TeV collected with the CMS detector at the LHC and corresponding to an integrated luminosity of 19.7 fbsup−1/sup. Excited leptons (ℓsup*/sup) produced via contact interactions in conjunction with a standard model lepton are considered, and a search is made for their gauge decay modes. The decays considered are ℓsup*/sup → ℓγ and ℓsup*/sup → ℓZ, which give final states of two leptons and a photon or, depending on the Z-boson decay mode, four leptons or two leptons and two jets. The number of events observed in data is consistent with the standard model prediction. Exclusion limits are set on the excited lepton mass, and the compositeness scale Λ. For the case Mℓ* = Λ the existence of excited electrons (muons) is excluded up to masses of 2.45 (2.47) TeV at 95% confidence level. Neutral current decays of excited leptons are considered for the first time, and limits are extended to include the possibility that the weight factors f and f′, which determine the couplings between standard model leptons and excited leptons via gauge mediated interactions, have opposite sign. © 2016, The Author(s).

Search for exotic cluster configurations in C-14 nucleus / Korotkova,LYu / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

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The analysis of 2-dimentional Dalitz' diagram, measured in C-14(pi(-), pd)X reaction, allowed to distinguish the pion absorption by (3)p intranuclear cluster and to obtain an indication on the existence of (3)p + Li-11 configuration in C-14 nucleus. Highly excited states of Be-12,Be-13 isotopes were found with the energy of E-x approximate to 30 MeV for the first time. It was shown that these states decay as follows Be-12* - p + Li-11 and Be-13* - d + Li-11.

Search for exotic decays of a Higgs boson into undetectable particles and one or more photons / Khachatryan,V. / Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 2016.

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A search is presented for exotic decays of a Higgs boson into undetectable particles and one or two isolated photons in pp collisions at a center-of-mass energy of 8 TeV. The data correspond to an integrated luminosity of up to 19.4 fb-1 collected with the CMS detector at the LHC. Higgs bosons produced in gluon-gluon fusion and in association with a Z boson are investigated, using models in which the Higgs boson decays into a gravitino and a neutralino or a pair of neutralinos, followed by the decay of the neutralino to a gravitino and a photon. The selected events are consistent with the background-only hypothesis, and limits are placed on the product of cross sections and branching fractions. Assuming a standard model Higgs boson production cross section, a 95% confidence level upper limit is set on the branching fraction of a 125 GeV Higgs boson decaying into undetectable particles and one or two isolated photons as a function of the neutralino mass. For this class of models and neutralino masses from 1 to 120 GeV an upper limit in the range of 7 to 13% is obtained. Further results are given as a function of the neutralino lifetime, and also for a range of Higgs boson masses. © 2015 CERN for the benefit of the CMS Collaboration.

Search for flavour-changing neutral current top-quark decays to q Z in pp collision data collected with the ATLAS detector at root s=8 TeV / Aad,G / EUROPEAN PHYSICAL JOURNAL C. - 2016.

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A search for the flavour-changing neutral-current decay is presented. Data collected by the ATLAS detector during 2012 from proton-proton collisions at the Large Hadron Collider at a centre-of-mass energy of root s = 8 TeV, corresponding to an integrated luminosity of 20.3 fb(-1), are analysed. Top-quark pair-production events with one top quark decaying through the t - qZ (q = u,c) channel and the other through the dominant Standard Model mode t - bW are considered as signal. Only the decays of the Z boson to charged leptons and leptonic W boson decays are used. No evidence for a signal is found and an observed (expected) upper limit on the t - qZ branching ratio of 7 x 10(-4) (8 x 10(-4)) is set at the 95 % confidence level.

Search for invisible decays of a Higgs boson using vector-boson fusion in pp collisions at (Formula Presented.) TeV with the ATLAS detector / TheATLAScollaboration / Journal of High Energy Physics. - 2016.

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A search for a Higgs boson produced via vector-boson fusion and decaying into invisible particles is presented, using 20.3 fbsup−1/sup of proton-proton collision data at a centre-of-mass energy of 8 TeV recorded by the ATLAS detector at the LHC. For a Higgs boson with a mass of 125 GeV, assuming the Standard Model production cross section, an upper bound of 0.28 is set on the branching fraction of H → invisible at 95% confidence level, where the expected upper limit is 0.31. The results are interpreted in models of Higgs-portal dark matter where the branching fraction limit is converted into upper bounds on the dark-matter-nucleon scattering cross section as a function of the dark-matter particle mass, and compared to results from the direct dark-matter detection experiments. © 2016, The Author(s).

Search for isobar-analog states of superheavy hydrogen isotopes He5-7 / Chernyshev,BA / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

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Search for isobar-analog states (IAS) of superheavy hydrogen isotopes H5-7 was performed among the high-excited states of helium isotopes He5-7. The excited spectra were measured in stopped pion absorption by light nuclei. The experiment was performed at low energy pion channel of LANL with two-arm multilayer semiconductor spectrometer. Excited states of He5-7 were observed in three-body reaction channels on B-10,B-11 nuclei. Several excited levels were observed for the first time. He-6 excited state with E-x = 27.0(8) MeV observed in B-10(pi(-), pt)X channel is an IAS candidate for H-6 with E-r similar to 5.5 MeV. He-7 excited state with E-x = 24.8(4) MeV observed in B-10(pi(-),pd)X, B-11(pi(-),pt)X and B-11(pi(-),dd)X channels is an IAS candidate for H-7 with E-r similar to 3 MeV.

Search for magnetic monopoles and stable particles with high electric charges in 8 TeV pp collisions with the ATLAS detector / Aad,G / PHYSICAL REVIEW D. - 2016.

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A search for highly ionizing particles produced in proton-proton collisions at 8 TeV center-of-mass energy is performed by the ATLAS Collaboration at the CERN Large Hadron Collider. The data set used corresponds to an integrated luminosity of 7.0 fb(-1). A customized trigger significantly increases the sensitivity, permitting a search for such particles with charges and energies beyond what was previously accessible. No events were found in the signal region, leading to production cross section upper limits in the mass range 200-2500 GeV for magnetic monopoles with magnetic charge in the range 0.5g(D) vertical bar g vertical bar 2.0g(D), where g(D) is the Dirac charge, and for stable particles with electric charge in the range 10 vertical bar z vertical bar 60. Model-dependent limits are presented in given pair-production scenarios, and model-independent limits are presented in fiducial regions of particle energy and pseudorapidity.

Search for massive WH resonances decaying into the ℓνbb¯ final state at √s = 8 TeV / Khachatryan,V. / European Physical Journal C. - 2016.

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A search for a massive resonance W sup′/supdecaying into a W and a Higgs boson in the ℓνb b ¯ (ℓ= e , μ) final state is presented. Results are based on data corresponding to an integrated luminosity of 19.7fb sup- 1/sup of proton–proton collisions at s= 8 TeV , collected using the CMS detector at the LHC. For a high-mass (≳ 1TeV) resonance, the two bottom quarks coming from the Higgs boson decay are reconstructed as a single jet, which can be tagged by placing requirements on its substructure and flavour. Exclusion limits at 95 % confidence level are set on the production cross section of a narrow resonance decaying into WH, as a function of its mass. In the context of a little Higgs model, a lower limit on the W sup′/sup mass of 1.4TeV is set. In a heavy vector triplet model that mimics the properties of composite Higgs models, a lower limit on the W sup′/sup mass of 1.5TeV is set. In the context of this model, the results are combined with related searches to obtain a lower limit on the W sup′/sup mass of 1.8TeV , the most restrictive to date for decays to a pair of standard model bosons. © 2016, CERN for the benefit of the CMS collaboration.

Search for Narrow Resonances Decaying to Dijets in Proton-Proton Collisions at root s=13 TeV / Khachatryan,V / PHYSICAL REVIEW LETTERS. - 2016.

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A search for narrow resonances in proton-proton collisions at root s = 13 TeV is presented. The invariant mass distribution of the two leading jets is measured with the CMS detector using a data set corresponding to an integrated luminosity of 2.4 fb(-1). The highest observed dijet mass is 6.1 TeV. The distribution is smooth and no evidence for resonant particles is observed. Upper limits at 95% confidence level are set on the production cross section for narrow resonances with masses above 1.5 TeV. When interpreted in the context of specific models, the limits exclude string resonances with masses below 7.0 TeV, scalar diquarks below 6.0 TeV, axigluons and colorons below 5.1 TeV, excited quarks below 5.0 TeV, color-octet scalars below 3.1 TeV, and W' bosons below 2.6 TeV. These results significantly extend previously published limits.

Search for narrow resonances in πp elastic scattering from the EPECUR experiment / Gridnev,A. / Physical Review C - Nuclear Physics. - 2016.

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The analysis of high-precision π±p→π±p cross-sectional data from the EPECUR Collaboration based on the multichannel K-matrix approach is presented. The sharp structures seen in these data are studied in terms of both opening thresholds and new resonance contributions. Some prominent features are found to be due to the opening KΣ channel. However, a complete description of the data is improved with the addition of two narrow resonant structures at W∼1.686 and W∼1.720GeV. These structures are interpreted as manifestations of S11 and P11 resonances. The underlying nature of the observed phenomena is discussed. © 2016 American Physical Society.

Search for neutral MSSM Higgs bosons decaying to μ+μ- in pp collisions at √s=7 and 8 TeV / Khachatryan,V. / Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 2016.

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A search for neutral Higgs bosons predicted in the minimal supersymmetric standard model (MSSM) for μ+μ- decay channels is presented. The analysis uses data collected by the CMS experiment at the LHC in proton-proton collisions at centre-of-mass energies of 7 and 8 TeV, corresponding to integrated luminosities of 5.1 and 19.3 fb-1, respectively. The search is sensitive to Higgs bosons produced either through the gluon fusion process or in association with a bb quark pair. No statistically significant excess is observed in the μ+μ- mass spectrum. Results are interpreted in the framework of several benchmark scenarios, and the data are used to set an upper limit on the MSSM parameter tanβ as a function of the mass of the pseudoscalar A boson in the range from 115 to 300 GeV. Model independent upper limits are given for the product of the cross section and branching fraction for gluon fusion and b quark associated production at s=8 TeV. They are the most stringent limits obtained to date in this channel. © 2015 The Authors.

Search for neutral resonances decaying into a Z boson and a pair of b jets or τ leptons / Khachatryan,V. / Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 2016.

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A search is performed for a new resonance decaying into a lighter resonance and a Z boson. Two channels are studied, targeting the decay of the lighter resonance into either a pair of oppositely charged τ leptons or a bb pair. The Z boson is identified via its decays to electrons or muons. The search exploits data collected by the CMS experiment at a centre-of-mass energy of 8 TeV, corresponding to an integrated luminosity of 19.8 fb-1. No significant deviations are observed from the standard model expectation and limits are set on production cross sections and parameters of two-Higgs-doublet models. © 2016 The Author.

Search for new phenomena in dijet mass and angular distributions from pp collisions at √s=13 TeV with the ATLAS detector / Aad,G. / Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 2016.

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This Letter describes a model-agnostic search for pairs of jets (dijets) produced by resonant and non-resonant phenomena beyond the Standard Model in 3.6 fbsup-1/sup of proton-proton collisions with a centre-of-mass energy of s=13 TeV recorded by the ATLAS detector at the Large Hadron Collider. The distribution of the invariant mass of the two leading jets is examined for local excesses above a data-derived estimate of the smoothly falling prediction of the Standard Model. The data are also compared to a Monte Carlo simulation of Standard Model angular distributions derived from the rapidity of the two jets. No evidence of anomalous phenomena is observed in the data, which are used to exclude, at 95% CL, quantum black holes with threshold masses below 8.3 TeV, 8.1 TeV, or 5.1 TeV in three different benchmark scenarios; resonance masses below 5.2 TeV for excited quarks, 2.6 TeV in a Wsup'/sup model, a range of masses starting from mZ'=1.5 TeV and couplings from gq=0.2 in a Zsup'/sup model; and contact interactions with a compositeness scale below 12.0 TeV and 17.5 TeV respectively for destructive and constructive interference between the new interaction and QCD processes. These results significantly extend the ATLAS limits obtained from 8 TeV data. Gaussian-shaped contributions to the mass distribution are also excluded if the effective cross-section exceeds values ranging from approximately 50-300 fb for masses below 2 TeV to 2-20 fb for masses above 4 TeV. © 2016 CERN for the benefit of the ATLAS Collaboration.

Search for new phenomena in events with at least three photons collected in pp collisions at √s = 8 TeV with the ATLAS detector / Aad,G. / European Physical Journal C. - 2016.

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Results of a search for new phenomena in events with at least three photons are reported. Data from proton–proton collisions at a centre-of-mass energy of 8 TeV, corresponding to an integrated luminosity of 20.3 fb (Formula presented.) , were collected with the ATLAS detector at the LHC. The observed data are well described by the Standard Model. Limits at the 95 % confidence level on new phenomena are presented based on the rate of events in an inclusive signal region and a restricted signal region targeting the rare decay (Formula presented.) , as well as di-photon and tri-photon resonance searches. For a Standard Model Higgs boson decaying to four photons via a pair of intermediate pseudoscalar particles (a), limits are found to be (Formula presented.) for 10 GeV (Formula presented.) 62 GeV. Limits are also presented for Higgs boson-like scalars (H) for (Formula presented.) 125 GeV, and for a (Formula presented.) decaying to three photons via (Formula presented.). Additionally, the observed limit on the branching ratio of the Z boson decay to three photons is found to be BR (Formula presented.) , a result five times stronger than the previous result from LEP. © 2016, CERN for the benefit of the ATLAS collaboration.

Search for new phenomena in final states with large jet multiplicities and missing transverse momentum with ATLAS using √s=13 TeV proton-proton collisions / Aad,G. / Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 2016.

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Results are reported of a search for new phenomena, such as supersymmetric particle production, that could be observed in high-energy proton-proton collisions. Events with large numbers of jets, together with missing transverse momentum from unobserved particles, are selected. The data analysed were recorded by the ATLAS experiment during 2015 using the 13 TeV centre-of-mass proton-proton collisions at the Large Hadron Collider, and correspond to an integrated luminosity of 3.2 fbsup-1/sup. The search selected events with various jet multiplicities from ≥7 to ≥10 jets, and with various b-jet multiplicity requirements to enhance sensitivity. No excess above Standard Model expectations is observed. The results are interpreted within two supersymmetry models, where gluino masses up to 1400 GeV are excluded at 95% confidence level, significantly extending previous limits. © 2016 CERN for the benefit of the ATLAS Collaboration.

Search for new phenomena with photon+jet events in proton-proton collisions at √s = 13 TeV with the ATLAS detector / TheATLAScollaboration / Journal of High Energy Physics. - 2016.

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Abstract: A search is performed for the production of high-mass resonances decaying into a photon and a jet in 3.2 fbsup−1/sup of proton-proton collisions at a centre-of-mass energy of (Formula presented.) TeV collected by the ATLAS detector at the Large Hadron Collider. Selected events have an isolated photon and a jet, each with transverse momentum above 150 GeV. No significant deviation of the γ+jet invariant mass distribution from the background-only hypothesis is found. Limits are set at 95% confidence level on the cross sections of generic Gaussian-shaped signals and of a few benchmark phenomena beyond the Standard Model: excited quarks with vector-like couplings to the Standard Model particles, and non-thermal quantum black holes in two models of extra spatial dimensions. The minimum excluded visible cross sections for Gaussian-shaped resonances with width-to-mass ratios of 2% decrease from about 6 fb for a mass of 1.5 TeV to about 0.8 fb for a mass of 5 TeV. The minimum excluded visible cross sections for Gaussian-shaped resonances with width-to-mass ratios of 15% decrease from about 50 fb for a mass of 1.5 TeV to about 1.0 fb for a mass of 5 TeV. Excited quarks are excluded below masses of 4.4 TeV, and non-thermal quantum black holes are excluded below masses of 3.8 (6.2) TeV for Randall-Sundrum (Arkani-Hamed-Dimopoulous-Dvali) models with one (six) extra dimensions.[Figure not available: see fulltext.] © 2016, The Author(s).

Search for pair production of first and second generation leptoquarks in proton-proton collisions at root s=8 TeV / Khachatryan,V / PHYSICAL REVIEW D. - 2016.

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A search for pair production of first and second generation leptoquarks is performed in final states containing either two charged leptons and two jets, or one charged lepton, one neutrino and two jets, using proton-proton collision data at root s = 8 TeV. The data, corresponding to an integrated luminosity of 19.7 fb(-1), were recorded with the CMS detector at the LHC. First-generation scalar leptoquarks with masses less than 1010 (850) GeV are excluded for beta = 1.0 (0.5), where beta is the branching fraction of a leptoquark decaying to a charged lepton and a quark. Similarly, second-generation scalar leptoquarks with masses less than 1080 (760) GeV are excluded for beta = 1.0 (0.5). Mass limits are also set for vector leptoquark production scenarios with anomalous vector couplings, and for R-parity violating supersymmetric scenarios of top squark pair production resulting in similar final-state signatures. These are the most stringent limits placed on the masses of vector leptoquarks and RPV top squarks to date.

Search for pair-produced vectorlike B quarks in proton-proton collisions at root s=8 TeV / Khachatryan,V / PHYSICAL REVIEW D. - 2016.

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A search for the production of a heavy B quark, having electric charge -1/3 and vector couplings to W, Z, and H bosons, is carried out using proton-proton collision data recorded at the CERN LHC by the CMS experiment, corresponding to an integrated luminosity of 19.7 fb(-1). The B quark is assumed to be pair produced and to decay in one of three ways: to tW, bZ, or bH. The search is carried out in final states with one, two, and more than two charged leptons, as well as in fully hadronic final states. Each of the channels in the exclusive final-state topologies is designed to be sensitive to specific combinations of the B quark-antiquark pair decays. The observed event yields are found to be consistent with the standard model expectations in all the final states studied. A statistical combination of these results is performed, and upper limits are set on the cross section of the strongly produced B quark-antiquark pairs as a function of the B quark mass. Lower limits on the B quark mass between 740 and 900 GeVare set at a 95% confidence level, depending on the values of the branching fractions of the B quark to tW, bZ, and bH. Overall, these limits are the most stringent to date.

Search for resonant t(t)over-bar production in proton-proton collisions at root s=8 TeV / Khachatryan,V / PHYSICAL REVIEW D. - 2016.

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A search is performed for the production of heavy resonances decaying into top-antitop quark pairs in proton-proton collisions at root s = 8 TeV. Data used for the analyses were collected with the CMS detector and correspond to an integrated luminosity of 19.7 fb(-1). The search is performed using events with three different final states, defined by the number of leptons (electrons and muons) from the t (t) over bar. WbWb decay. The analyses are optimized for reconstruction of top quarks with high Lorentz boosts, where jet substructure techniques are used to enhance the sensitivity. Results are presented for all channels and a combination is performed. No significant excess of events relative to the expected yield from standard model processes is observed. Upper limits on the production cross section of heavy resonances decaying to t (t) over bar are calculated. A narrow leptophobic topcolor Z' resonance with a mass below 2.4 TeV is excluded at 95% confidence level. Limits are also derived for a broad Z' resonance with a 10% width relative to the resonance mass, and a Kaluza-Klein excitation of the gluon in the Randall-Sundrum model. These are the most stringent limits to date on heavy resonances decaying into top-antitop quark pairs.

Search for single production of a vector-like quark via a heavy gluon in the 4b final state with the ATLAS detector in pp collisions at s=8 TeV / Aad,G. / Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 2016.

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A search is performed for the process pp→G*→BHb-/B-Hb→Hbb-→bb-bb-, predicted in composite Higgs scenarios, where Gsup*/sup is a heavy colour octet vector resonance and BH a vector-like quark of charge -1/3. The data were obtained from pp collisions at a centre-of-mass energy of 8 TeV corresponding to an integrated luminosity of 19.5 fbsup-1/sup, recorded by the ATLAS detector at the LHC. The largest background, multijet production, is estimated using a data-driven method. No significant excess of events with respect to Standard Model predictions is observed, and upper limits on the production cross section times branching ratio are set. Comparisons to the predictions from a specific benchmark model are made, resulting in lower mass limits in the two-dimensional mass plane of mG* vs. mBH. © 2016 The Author.

Search for single production of scalar leptoquarks in proton-proton collisions at root s=8 TeV / Khachatryan,V/ PHYSICAL REVIEW D. - 2016.

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A search is presented for the production of both first- and second-generation scalar leptoquarks with a final state of either two electrons and one jet or two muons and one jet. The search is based on a data sample of proton-proton collisions at center-of-mass energy root s = 8 TeV recorded with the CMS detector and corresponding to an integrated luminosity of 19.6 fb(-1). Upper limits are set on both the first- and second-generation leptoquark production cross sections as functions of the leptoquark mass and the leptoquark couplings to a lepton and a quark. Results are compared with theoretical predictions to obtain lower limits on the leptoquark mass. At 95% confidence level, single production of first- generation leptoquarks with a coupling and branching fraction of 1.0 is excluded for masses below 1730 GeV, and second-generation leptoquarks with a coupling and branching fraction of 1.0 is excluded for masses below 530 GeV. These are the best overall limits on the production of first-generation leptoquarks to date.

Search for single top-quark production via flavour-changing neutral currents at 8TeV with the ATLAS detector / Aad,G / EUROPEAN PHYSICAL JOURNAL C. - 2016.

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A search for single top-quark production via flavour-changing neutral current processes from gluon plus up- or charm-quark initial states in proton-proton collisions at the LHC is presented. Data collected with the ATLAS detector in 2012 at a centre-of-mass energy of 8TeV and corresponding to an integrated luminosity of 20.3 fb(-1) are used. Candidate events for a top quark decaying into a lepton, a neutrino and a jet are selected and classified into signal- and background-like candidates using a neural network. No signal is observed and an upper limit on the production cross-section multiplied by the t - Wb branching fraction is set. The observed 95% CL limit is sigma(qg - t) x B(t - Wb) 3.4 pb and the expected 95% CL limit is sigma(qg - t) x B(t - Wb) 2.9 pb. The observed limit can be interpreted as upper limits on the coupling constants of the flavour-changing neutral current interactions divided by the scale of new physics kappa(ugt)/Lambda 5.8 x 10(-3) TeV-1 and kappa(cgt)/Lambda 13x10(-3) TeV and on the branching fractions B(t - ug) 4.0 x 10(-5) and B(t - cg) 20 x 10(-5).

Search for strong gravity in multijet final states produced in pp collisions at √s = 13 TeV using the ATLAS detector at the LHC / TheATLAScollaboration / Journal of High Energy Physics. - 2016.

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Abstract: A search is conducted for new physics in multijet final states using 3.6 inverse femtobarns of data from proton-proton collisions at (Formula presented.) TeV taken at the CERN Large Hadron Collider with the ATLAS detector. Events are selected containing at least three jets with scalar sum of jet transverse momenta (HT) greater than 1 TeV. No excess is seen at large HT and limits are presented on new physics: models which produce final states containing at least three jets and having cross sections larger than 1.6 fb with HT> 5.8 TeV are excluded. Limits are also given in terms of new physics models of strong gravity that hypothesize additional space-time dimensions.[Figure not available: see fulltext.] © 2016, The Author(s).

Search for supersymmetry at √s= 13 TeV in final states with jets and two same-sign leptons or three leptons with the ATLAS detector / AtlasCollaboration / European Physical Journal C. - 2016.

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A search for strongly produced supersymmetric particles is conducted using signatures involving multiple energetic jets and either two isolated leptons (e or μ) with the same electric charge or at least three isolated leptons. The search also utilises b-tagged jets, missing transverse momentum and other observables to extend its sensitivity. The analysis uses a data sample of proton–proton collisions at √s= 13 TeV recorded with the ATLAS detector at the Large Hadron Collider in 2015 corresponding to a total integrated luminosity of 3.2 fbsup-1/sup. No significant excess over the Standard Model expectation is observed. The results are interpreted in several simplified supersymmetric models and extend the exclusion limits from previous searches. In the context of exclusive production and simplified decay modes, gluino masses are excluded at 95 % confidence level up to 1.1–1.3 TeV for light neutralinos (depending on the decay channel), and bottom squark masses are also excluded up to 540 GeV. In the former scenarios, neutralino masses are also excluded up to 550–850 GeV for gluino masses around 1 TeV. © 2016, CERN for the benefit of the ATLAS collaboration.

Search for supersymmetry in electroweak production with photons and large missing transverse energy in pp collisions at √s=8TeV / Khachatryan,V. / Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 2016.

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Results are reported from a search for supersymmetry with gauge-mediated supersymmetry breaking in electroweak production. Final states with photons and large missing transverse energy ( ET supmiss/sup) were examined. The data sample was collected in pp collisions at √s=8TeV with the CMS detector at the LHC and corresponds to 7.4fbsup-1/sup. The analysis focuses on scenarios in which the lightest neutralino has bino- or wino-like components, resulting in decays to photons and gravitinos, where the gravitinos escape undetected. The data were obtained using a specially designed trigger with dedicated low thresholds, providing good sensitivity to signatures with photons, ET supmiss/sup, and low hadronic energy. No excess of events over the standard model expectation is observed. The results are interpreted using the model of general gauge mediation. With the wino mass fixed at 10GeV above that of the bino, wino masses below 710GeV are excluded at 95% confidence level. Constraints are also set in the context of two simplified models, for which the analysis sets the lowest cross section limits on the electroweak production of supersymmetric particles. © 2016 The Author.

Search for supersymmetry in events with a photon, a lepton, and missing transverse momentum in pp collisions at s=8 TeV / Khachatryan,V. / Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 2016.

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A search for supersymmetry involving events with at least one photon, one electron or muon, and large missing transverse momentum has been performed by the CMS experiment. The data sample corresponds to an integrated luminosity of 19.7 fbsup-1/sup of pp collisions at s=8 TeV, produced at the CERN LHC. No excess of events is observed beyond expectations from standard model processes. The result of the search is interpreted in the context of a general model of gauge-mediated supersymmetry breaking, where the charged and neutral winos are the next-to-lightest supersymmetric particles. Within this model, winos with a mass up to 360 GeV are excluded at the 95% confidence level. Two simplified models inspired by gauge-mediated supersymmetry breaking are also examined, and used to derive upper limits on the production cross sections of specific supersymmetric processes. © 2016 CERN for the benefit of the CMS Collaboration.

Search for supersymmetry in events with soft leptons, low jet multiplicity, and missing transverse energy in proton-proton collisions at s=8 TeV / Khachatryan,V. / Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 2016.

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Results are presented from a search for supersymmetric particles in scenarios with small mass splittings. The data sample corresponds to 19.7 fbsup-1/sup of proton-proton collisions recorded by the CMS experiment at s=8 TeV. The search targets top squark (t~) pair production in scenarios with mass differences δm=m(t~)-m(χ~10) below the W-boson mass and with top-squark decays in the four-body mode (t~→bℓνχ~10), where the neutralino (χ~10) is assumed to be the lightest supersymmetric particle (LSP). The signature includes a high transverse momentum (pT) jet associated with initial-state radiation, one or two low-pT leptons, and significant missing transverse energy. The event yields observed in data are consistent with the expected background contributions from standard model processes. Limits are set on the cross section for top squark pair production as a function of the t~ and LSP masses. Assuming a 100% branching fraction for the four-body decay mode, top-squark masses below 316 GeV are excluded for δm=25 GeV at 95% CL. The dilepton data are also interpreted under the assumption of chargino-neutralino production, with subsequent decays to sleptons or sneutrinos. Assuming a difference between the common χ~1+/χ~20 mass and the LSP mass of 20 GeV and a τ-enriched decay scenario, masses in the range m(χ~1+)<307 GeV are excluded at 95% CL. © 2016 The Author.

Search for supersymmetry in pp collisions at root s=8 TeV in final states with boosted W bosons and b jets using razor variables / Khachatryan,V / PHYSICAL REVIEW D. - 2016.

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A search for supersymmetry in hadronic final states with highly boosted W bosons and b jets is presented, focusing on compressed scenarios. The search is performed using proton-proton collision data at a center-of-mass energy of 8 TeV, collected by the CMS experiment at the LHC, corresponding to an integrated luminosity of 19.7 fb(-1). Events containing candidates for hadronic decays of boosted W bosons are identified using jet substructure techniques, and are analyzed using the razor variables M-R and R-2, which characterize a possible signal as a peak on a smoothly falling background. The observed event yields in the signal regions are found to be consistent with the expected contributions from standard model processes, which are predicted using control samples in the data. The results are interpreted in terms of gluino-pair production followed by their exclusive decay into top squarks and top quarks. The analysis excludes gluino masses up to 1.1 TeV for light top squarks decaying solely to a charm quark and a neutralino, and up to 700 GeV for heavier top squarks decaying solely to a top quark and a neutralino.

Search for supersymmetry in the multijet and missing transverse momentum final state in pp collisions at 13 TeV / Khachatryan,V. / Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 2016.

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A search for new physics is performed based on all-hadronic events with large missing transverse momentum produced in proton-proton collisions at s=13 TeV. The data sample, corresponding to an integrated luminosity of 2.3 fbsup-1/sup, was collected with the CMS detector at the CERN LHC in 2015. The data are examined in search regions of jet multiplicity, tagged bottom quark jet multiplicity, missing transverse momentum, and the scalar sum of jet transverse momenta. The observed numbers of events in all search regions are found to be consistent with the expectations from standard model processes. Exclusion limits are presented for simplified supersymmetric models of gluino pair production. Depending on the assumed gluino decay mechanism, and for a massless, weakly interacting, lightest neutralino, lower limits on the gluino mass from 1440 to 1600 GeV are obtained, significantly extending previous limits. © 2016 The Author.

Search for the electroweak production of supersymmetric particles in √s = 8 TeV pp collisions with the ATLAS detector / Aad,G./ Physical Review D - Particles, Fields, Gravitation and Cosmology. - 2016.

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The ATLAS experiment has performed extensive searches for the electroweak production of charginos, neutralinos, and staus. This article summarizes and extends the search for electroweak supersymmetry with new analyses targeting scenarios not covered by previously published searches. New searches use vector-boson fusion production, initial-state radiation jets, and low-momentum lepton final states, as well as multivariate analysis techniques to improve the sensitivity to scenarios with small mass splittings and low-production cross sections. Results are based on 20 fbsup-1/sup of proton-proton collision data at √s = 8 TeV recorded with the ATLAS experiment at the Large Hadron Collider. No significant excess beyond Standard Model expectations is observed. The new and existing searches are combined and interpreted in terms of 95% confidence-level exclusion limits in simplified models, where a single production process and decay mode is assumed, as well as within phenomenological supersymmetric models. © 2016 CERN, for the ATLAS Collaboration. Published by the American Physical Society under the terms of the "http://creativecommons.org/licenses/by/3.0/" Creative Commons Attribution 3.0 License. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.

Search for the production of an excited bottom quark decaying to tW in proton-proton collisions at (Formula Presented.) TeV / TheCMScollaboration / Journal of High Energy Physics. - 2016.

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A search is presented for a singly produced excited bottom quark (bsup*/sup) decaying to a top quark and a W boson in the all-hadronic, lepton+jets, and dilepton final states in proton-proton collisions at s=8(Formula Presented.)TeV recorded by the CMS experiment at the CERN LHC. Data corresponding to an integrated luminosity of 19.7 fbsup−1/sup are used. No significant excess of events is observed with respect to standard model expectations. We set limits at 95% confidence on the product of the bsup*/sup quark production cross section and its branching fraction to tW. The cross section limits are interpreted for scenarios including left-handed, right-handed, and vector-like couplings of the bsup*/sup quark and are presented in the two-dimensional coupling plane based on the production and decay coupling constants. The masses of the left-handed, right-handed, and vector-like bsup*/sup quark states are excluded at 95% confidence below 1390, 1430, and 1530 GeV, respectively, for benchmark couplings. This analysis gives the most stringent limits on the mass of the bsup∗/sup quark to date.[Figure not available: see fulltext.] © 2016, The Author(s).

Search for the production of single vector-like and excited quarks in the Wt final state in pp collisions at √s = 8 TeV with the ATLAS detector / TheATLAScollaboration / Journal of High Energy Physics. - 2016.

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A search for vector-like quarks and excited quarks in events containing a top quark and a W boson in the final state is reported here. The search is based on 20.3 fbsup−1/sup of proton-proton collision data taken at the LHC at a centre-of-mass energy of 8 TeV recorded by the ATLAS detector. Events with one or two leptons, and one, two or three jets are selected with the additional requirement that at least one jet contains a b-quark. Single-lepton events are also required to contain at least one large-radius jet from the hadronic decay of a high-pTW boson or a top quark. No significant excess over the expected background is observed and upper limits on the cross-section times branching ratio for different vector-like quark and excited-quark model masses are derived. For the excited-quark production and decay to Wt with unit couplings, quarks with masses below 1500 GeV are excluded and coupling-dependent limits are set. © 2016, The Author(s).

Search for the rare decay D0 →γγ at Belle / Nisar,N.K. / Physical Review D - Particles, Fields, Gravitation and Cosmology. - 2016.

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We search for the rare radiative decay D0→γγ using a data sample with an integrated luminosity of 832 fb-1 recorded by the Belle detector at the KEKB e+e- asymmetric-energy collider. We find no statistically significant signal and set an upper limit on the branching fraction of B(D0→γγ)<8.5×10-7 at 90% confidence level. This is the most restrictive limit on the decay channel to date. © 2016 American Physical Society.

Search for the Standard Model Higgs boson decaying into bbЇ produced in association with top quarks decaying hadronically in pp collisions at √s = 8 TeV with the ATLAS detector / TheATLAScollaboration,CERN / Journal of High Energy Physics. - 2016.

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A search for Higgs boson production in association with a pair of top quarks (tt¯ H) is performed, where the Higgs boson decays to bb¯, and both top quarks decay hadronically. The data used correspond to an integrated luminosity of 20.3 fb−1 of pp collisions at √s = 8 TeV collected with the ATLAS detector at the Large Hadron Collider. The search selects events with at least six energetic jets and uses a boosted decision tree algorithm to discriminate between signal and Standard Model background. The dominant multijet background is estimated using a dedicated data-driven technique. For a Higgs boson mass of 125 GeV, an upper limit of 6.4 (5.4) times the Standard Model cross section is observed (expected) at 95% confidence level. The best-fit value for the signal strength is μ = 1.6 ± 2.6 times the Standard Model expectation for mH = 125 GeV. Combining all tt¯ H searches carried out by ATLAS at √s = 8 and 7 TeV, an observed (expected) upper limit of 3.1 (1.4) times the Standard Model expectation is obtained at 95% confidence level, with a signal strength μ = 1.7 ± 0.8. © 2016, The Author(s).

Search for the standard model Higgs boson produced in association with a vector boson and decaying into a tau pair in pp collisions at root s=8 TeV with the ATLAS detector / Aad,G / PHYSICAL REVIEW D. - 2016.

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A search for the standard model Higgs boson produced in association with a vector boson with the decay H - tau tau is presented. The data correspond to 20.3 fb(-1) of integrated luminosity from proton-proton collisions at root s = 8 TeV recorded by the ATLAS experiment at the LHC during 2012. The data agree with the background expectation, and 95% confidence-level upper limits are placed on the cross section of this process. The observed (expected) limit, expressed in terms of the signal strength mu= sigma/sigma(SM) for m(H) = 125 GeV, is mu 5.6 (3.7). The measured value of the signal strength is mu

Search for vectorlike charge 2/3 T quarks in proton-proton collisions at root(s)=8 TeV / Khachatryan,V / PHYSICAL REVIEW D. - 2016.

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A search for fermionic top quark partners T of charge 2/3 is presented. The search is carried out in proton-proton collisions corresponding to an integrated luminosity of 19.7 fb(-1) collected at a center-of-mass energy of root s = 8 TeV with the CMS detector at the LHC. The T quarks are assumed to be produced strongly in pairs and can decay into tH, tZ, and bW. The search is performed in five exclusive channels: a single-lepton channel, a multilepton channel, two all-hadronic channels optimized either for the bW or the tH decay, and one channel in which the Higgs boson decays into two photons. The results are found to be compatible with the standard model expectations in all the investigated final states. A statistical combination of these results is performed and lower limits on the T quark mass are set. Depending on the branching fractions, lower mass limits between 720 and 920 GeV at 95% confidence level are found. These are among the strongest limits on vectorlike T quarks obtained to date.

Search for W ' - tb in proton-proton collisions at root s=8 TeV / Khachatryan,V / JOURNAL OF HIGH ENERGY PHYSICS. - 2016

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A search is performed for the production of a massive W' boson decaying to a top and a bottom quark. The data analysed correspond to an integrated luminosity of 19.71 fb(-1) collected with the CMS detector at the LHC in proton-proton collisions at root s = 8 TeV. The hadronic decay products of the top quark with high Lorentz boost from the W' boson decay are detected as a single top flavoured jet. The use of jet substructure algorithms allows the top quark jet to be distinguished from standard model QCD background. Limits on the production cross section of a right-handed W' boson are obtained, together with constraints on the left-handed and right-handed couplings of the W' boson to quarks. The production of a right-handed W' boson with a mass below 2.02 TeV decaying to a hadronic final state is excluded at 95% confidence level. This mass limit increases to 2.15 TeV when both hadronic and leptonic decays are considered, and is the most stringent lower mass limit to date in the tb decay mode.

Search for W' decaying to tau lepton and neutrino in proton-proton collisions at s=8 TeV / Khachatryan,V. / Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 2016.

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The first search for a heavy charged vector boson in the final state with a tau lepton and a neutrino is reported, using 19.7 fb-1 of LHC data at s=8 TeV. A signal would appear as an excess of events with high transverse mass, where the standard model background is low. No excess is observed. Limits are set on a model in which the W' decays preferentially to fermions of the third generation. These results substantially extend previous constraints on this model. Masses below 2.0 to 2.7 TeV are excluded, depending on the model parameters. In addition, the existence of a W' boson with universal fermion couplings is excluded at 95% confidence level, for W' masses below 2.7 TeV. For further reinterpretation a model-independent limit on potential signals for various transverse mass thresholds is also presented. © 2016 CERN for the benefit of the CMS Collaboration.

Search for weakly decaying Λn and ΛΛ exotic bound states in central Pb-Pb collisions at sNN=2.76 TeV / Adam,J. / Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 2016.

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We present results of a search for two hypothetical strange dibaryon states, i.e. the H-dibaryon and the possible Λn bound state. The search is performed with the ALICE detector in central (0-10%) Pb-Pb collisions at sNN=2.76 TeV, by invariant mass analysis in the decay modes Λn→dπ+ and H-dibaryon →Λpπ-. No evidence for these bound states is observed. Upper limits are determined at 99% confidence level for a wide range of lifetimes and for the full range of branching ratios. The results are compared to thermal, coalescence and hybrid UrQMD model expectations, which describe correctly the production of other loosely bound states, like the deuteron and the hypertriton. © 2015 The Authors.

Search of predictors of geoeffective heliospheric events by means of muon hodoscope URAGAN / Shutenko,VV / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

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The flux of charged primary cosmic rays (PCR) is modulated by changes of interplanetary magnetic field which depend on various heliospheric processes. After interaction of PCR with nuclei of atoms of the Earth's atmosphere, these modulations are transferred to a flux of secondary muons. Muon hodoscope URAGAN allows to trace changes not only of intensity of the muon flux, but also its angular distribution in a wide range of zenith angles (080). Some results of searching of predictors of geoeffective heliospheric events by means of muon hodoscope URAGAN are presented.

Charged particle production in Pb-Pb and p-Pb collisions measured by the ATLAS detector / Shulga,Evgeny / 15TH INTERNATIONAL CONFERENCE ON STRANGENESS IN QUARK MATTER (SQM2015). - 2016.

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The ATLAS experiment at the Large Hadron Collider measures charged hadron spectra in Pb+Pb and p+Pb collisions. The results are compared to the pp spectra of charged hadrons at the same centre-of-mass energy. Charged hadron distributions from Pb+Pb are compared to charged particle cross-sections in pp collisions at root s = 2.76 TeV, reference crosssection for p+Pb at root s(NN) = 5.02 TeV is reconstructed using root s = 2.76 TeV and 7 TeV pp results. These allow for a detailed comparison of the collision systems in a wide transverse momentum and rapidity ranges in different centrality intervals. The nuclear modification factors RAA and Rppb are presented as a function of centrality, P-T, eta. The charged particle R-AA is found to vary significantly as a function of transverse momentum, and shows a pronounced minimum at about 7 GeV. Above 60 GeV, R-AA is consistent with a flat, centrality-dependent, value within the uncertainties. R-pPb results show strong rapidity dependence in the region of so-called Cronin peak at about 2 GeV and above pr of 10 GeV show anomalous enhancement.

Software tool for xenon gamma-ray spectrometer control / Chernysheva,IV / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

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Software tool "Acquisition and processing of gamma-ray spectra" for xenon gamma-ray spectrometers control was developed. It supports the multi-windows interface. Software tool has the possibilities for acquisition of gamma-ray spectra from xenon gamma-ray detector via USB or RS-485 interfaces, directly or via TCP-IP protocol, energy calibration of gamma-ray spectra, saving gamma-ray spectra on a disk.

Solar X-ray polarimetry and spectrometry instrument PING-M for the Interhelioprobe mission / Dergachev,V.A. / Advances in Space Research. - 2016.

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The PING-M experiment is designed to investigate solar X-ray activity. The instrument includes a hard X-ray polarimeter (PING-P), a hard X-ray spectrometer (HXRS) and a soft X-ray spectrometer (SXRS). PING-P has the energy range of 20-150keV and an effective area of about 2.5cmsup2/sup. It uses three organic scintillation detectors as active scatterers, which work in coincidence with six absorber detectors, based on CsI(Tl) scintillator. This technique allows us to considerably improve the polarimeter sensitivity. HXRS has the energy range of 20-600keV and an effective area of about 15cmsup2/sup. It is based on a fast inorganic scintillator (LaBr3(Ce) or CeBr3) with a relatively high energy resolution of 3.5-4.5% at 662keV. The SXRS energy range is 1.5-25keV, and its aperture is ø0.1mm, which provides the registration of solar flares in the range from C1 to X20 class of GOES scale. It is based on a SDD semiconductor detector with an energy resolution better than 200eV at 5.9keV line. The experiment will be performed onboard the Russian interplanetary mission Interhelioprobe which is planned for launch after 2025.The instrument will allow us to investigate angular and energy distributions of accelerated electrons, plasma heating processes, etc. Stereoscopic polarimetry and spectrometric observations will be possible if a similar instrument is installed onboard a near Earth satellite, or the second probe of the Interhelioprobe mission. © 2016 COSPAR.

Performance of the pair spectrometer of the GlueX experiment / Somov,A, Somov,S, Tolstukhin,I / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

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The description of the pair spectrometer of the GlueX detector at Jefferson Lab and its performance during the first beam commissioning runs are presented. We measured the amount of light collected from each channel of the pair spectrometer hodoscopes and the time resolution of the pair spectrometer counters.

P-odd effects in heavy ion collisions at NICA / Sorin,A., Teryaev,O. / Nuclear and Particle Physics Proceedings. - 2016.

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Experimental manifestation of P-odd effects related to the vorticity and hydrodynamic helicity in non-central heavy ion collisions at MPD@NICA and BM@N detectors is discussed. For the NICA and FAIR energy range characterized by the large baryonic charge of the forming medium the effect should manifest itself in the specific neutron asymmetries. The polarization of strange particles probing the vorticity and helicity is also discussed. © 2015 Elsevier B.V.

SOX: Short Distance Neutrino Oscillations with Borexino / Bravo-Berguсo,D. / Nuclear and Particle Physics Proceedings. - 2016.

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The Borexino detector has convincingly shown its outstanding performance in the in the sub-MeV regime through its unprecedented accomplishments in the solar and geo-neutrinos detection, which make it the ideal tool to unambiguously test the long-standing issue of the existence of a sterile neutrino, as suggested by several anomalies: the outputs of the LSND and Miniboone experiments, the results of the source calibration of the two Gallium solar ν experiments, and the recently hinted reactor anomaly. The SOX project will exploit two sources, based on chromium and cerium, which deployed under the experiment will emit two intense beams of νe (Cr) and νe (Ce). Interacting in the active volume of the liquid scintillator, each beam would create a spatial wave pattern in case of oscillation of the νe (or νe) into the sterile state, which would be the smoking gun proving the existence of the new sterile member of the neutrino family. Otherwise, its absence will allow setting very stringent limit on its existence. © 2015.

Spatial distribution of Cherenkov light from cascade showers in water / Khomyakov,VA [и др.] // INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

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The analysis of spatial distribution of Cherenkov light generated by cascade showers in Cherenkov water detector (CWD) NEVOD was performed. Showers generated by nearly horizontal muons were selected. Muons tracks were reconstructed with high precision using the coordinate tracking detector DECOR. For the first time, the dependence of Cherenkov light intensity on the depth of a shower at different distances from its axis was measured.

Structural Characteristics and Thermophysical Properties of Complex Ceramic Oxides in the System Dysub2/subOsub3/sub–HfOsub2/sub / Zubavichus,Y.V. / Glass and Ceramics (English translation of Steklo i Keramika). - 2016.

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The structure and thermophysical properties of materials formed in the system Dy2O3–HfO2 (molar ratio 1 : 3 to 3 : 1) as a result of isothermal firing of x-ray amorphous mixed hydroxides at temperature to 1600°C are investigated. It is shown that for ratios 1 : 3 to 1 : 1 the crystallization process results in the formation of single-phase solid solutions with the structure of defective fluorite and marked nonequivalence of the parameters of the local environment of the Dy and Hf atoms. It is determined that the ceramic based on dysprosium hafnate (Dy2O3: HfO2 = 1 : 1) possesses low, practically temperature independent (to 800°C), thermal conductivity about 1.4 W/(m · K). © 2016 Springer Science+Business Media New York

Structure–phase transformations and physical properties of ferritic–martensitic 12% chromium steels EK-181 and ChS-139 / Potapenko,M.M. / Technical Physics. - 2016.

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The thermophysical properties (specific heat, thermal diffusivity, thermal conductivity, linear thermal expansion coefficient, density) of 12% chromium ferritic–martensitic steels EK-181 (RUSFER-EK-181) and ChS-139 and the structure–phase transformations that occur in them upon heating and cooling in the temperature range 20–1100°C are studied. The temperatures of the start and finish of the α → γ and γ → α transformations in these steels and the Curie temperature are determined by differential scanning calorimetry. Peaks in the temperature dependence of the specific heat and jumplike changes in the linear thermal expansion coefficient and the density and the minimum of thermal diffusivity are detected in the α → γ transformation range. Specific heat peaks, thermal conductivity minima, and inflection points in thermal diffusivity curves are also observed near the Curie temperature. © 2016, Pleiades Publishing, Ltd.

Studies of the possibility to use Gas Pixel Detector as a fast trigger tracking device / Sinev,N / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

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Gas Pixel Detector (GPD) technology offers new possibilities, which make them very attractive for application in existing and future accelerator experiments and beyond. GPDs combine advantages of silicon and gaseous detectors. They can be produced radiation hard and with low power consumption using relatively cheap technology. Low capacitance of the individual pixel channel allows us to obtain a large signal to noise ratio. Using a time projection method for GPD readout one obtains 3D track image with precise coordinate (31 rim) and angular information (0.40 degrees). This feature would allow us to achieve performance of one GPD layer equal to a few layers of silicon detectors. Implementation of a fast readout and data processing at the front-end level allows one to reconstruct a track segment in less than 1 his, and to use this information for the first level trigger generation. The relevant algorithms of data acquisition and analysis are described and the results of simulations are presented in this paper.

Studies with cathode drift chambers for the GlueX experiment at Jefferson Lab / Pentchev,L. / Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment. - 2016.

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A drift chamber system consisting of 24 1m-diameter chambers with both cathode and wire readout (total of 12,672 channels) is operational in Hall D at Jefferson Lab (Virginia). Two cathode strip planes and one wire plane in each chamber register the same avalanche allowing the study of avalanche development, charge induction process, and strip resolution. We demonstrate a method for reconstructing the two-dimensional distribution of the avalanche "center-of-gravity" position around the wire from an sup55/supFe source with resolutions down to 30μm. We estimate the azimuthal extent of the avalanche around the wire as a function of the total charge for an Ar/CO2 gas mixture. By means of cluster counting using a modified 3cm-gap chamber, we observe significant space charge effects within the same track, resulting in an extent of the avalanche along the wire. © 2016.

Study of B Meson Production in p+Pb Collisions at √ssubNN/sub = 5.02 TeV Using Exclusive Hadronic Decays / Khachatryan,V. / Physical Review Letters. - 2016.

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The production cross sections of the Bsup+/sup, Bsup0/sup, and Bs sup0/sup mesons, and of their charge conjugates, are measured via exclusive hadronic decays in p+Pb collisions at the center-of-mass energy √SNN = 5.02 TeV with the CMS detector at the CERN LHC. The data set used for this analysis corresponds to an integrated luminosity of 34.6 nbsup-1/sup. The production cross sections are measured in the transverse momentum range between 10 and 60 GeV/c. No significant modification is observed compared to proton-proton perturbative QCD calculations scaled by the number of incoherent nucleon-nucleon collisions. These results provide a baseline for the study of in-medium b quark energy loss in Pb+Pb collisions. © 2016 CERN.

Study of B-0 - rho(+)rho(-) decays and implications for the CKM angle phi(2) / Vanhoefer,P / PHYSICAL REVIEW D. - 2016.

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We present a measurement of the branching fraction and the longitudinal polarization fraction of B-0 - rho(+)rho(-) decays, as well as the time-dependent CP violating parameters in decays into longitudinally polarized rho(+)rho(-) pairs with Belle's final data set of 772 x 10(6) B (B) over bar pairs, at the Upsilon(4S) resonance, collected at the asymmetric-energy e(+)e(-) collider KEKB. We obtain B(B-0 - rho(+)rho(-)) = (28.3 +/- 1.5(stat) +/- 1.5(syst)) x 10(-6), f(L) = 0.988 +/- 0.012(stat) +/- 0.023(syst), A(CP) = 0.00 +/- 0.10(stat) +/- 0.06(syst), S-CP = -0.13 +/- 0.15(stat) +/- 0.05(syst). We perform an isospin analysis to constrain the Cabibbo-Kobayashi-Maskawa angle phi(2) and obtain two solutions with phi(2) = (93.7 +/- 10.6)degrees, being most compatible with other Standard-Model based fits to the data.

Study of cosmic ray events with high muon multiplicity using the ALICE detector at the CERN Large Hadron Collider / Adam,J. / Journal of Cosmology and Astroparticle Physics. - 2016.

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ALICE is one of four large experiments at the CERN Large Hadron Collider near Geneva, specially designed to study particle production in ultra-relativistic heavy-ion collisions. Located 52 meters underground with 28 meters of overburden rock, it has also been used to detect muons produced by cosmic ray interactions in the upper atmosphere. In this paper, we present the multiplicity distribution of these atmospheric muons and its comparison with Monte Carlo simulations. This analysis exploits the large size and excellent tracking capability of the ALICE Time Projection Chamber. A special emphasis is given to the study of high multiplicity events containing more than 100 reconstructed muons and corresponding to a muon areal density ρμ > 5.9 msup-2/sup. Similar events have been studied in previous underground experiments such as ALEPH and DELPHI at LEP. While these experiments were able to reproduce the measured muon multiplicity distribution with Monte Carlo simulations at low and intermediate multiplicities, their simulations failed to describe the frequency of the highest multiplicity events. In this work we show that the high multiplicity events observed in ALICE stem from primary cosmic rays with energies above 10sup16/sup eV and that the frequency of these events can be successfully described by assuming a heavy mass composition of primary cosmic rays in this energy range. The development of the resulting air showers was simulated using the latest version of QGSJET to model hadronic interactions. This observation places significant constraints on alternative, more exotic, production mechanisms for these events. © 2016 CERN for the benefit of the ALICE Collaboration.

Study of nuclear multifragmentation induced by ultrarelativistic mu-mesons in nuclear track emulsion / Bradnova,V / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

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Exposures of test samples of nuclear track emulsion were analyzed. The formation of high-multiplicity nuclear stars was observed upon irradiating nuclear track emulsions with ultrarelativistic muons. Kinematical features studied in this exposure of nuclear track emulsions for events of the muon-induced splitting of carbon nuclei to three cr-particles are indicative of the nuclear-diffraction interaction mechanism.

Study of pi(0) pair production in single-tag two-photon collisions / Masuda,M / PHYSICAL REVIEW D. - 2016.

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We report a measurement of the differential cross section of pi(0) pair production in single-tag two-photon collisions, gamma*gamma - pi(0) pi(0), in e(+) e(-) scattering. The cross section is measured for Q(2) up to 30 GeV2, where Q(2) is the negative of the invariant mass squared of the tagged photon, in the kinematic range 0.5 GeV W 2.1 GeV and vertical bar cos theta*vertical bar 1.0 for the total energy and pion scattering angle, respectively, in the gamma*gamma center-of-mass system. The results are based on a data sample of 759 fb(-1) collected with the Belle detector at the KEKB asymmetric-energy e(+) e(-) collider. The transition form factor of the f(0)(980) and that of the f(2)(1270) with the helicity-0, -1, and -2 components separately are measured for the first time and are compared with theoretical calculations.

Study of the (Formula presented.) and (Formula presented.) decays with the ATLAS detector / Aad,G. / European Physical Journal C. - 2016.

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The decays (Formula presented.) and (Formula presented.) are studied with the ATLAS detector at the LHC using a dataset corresponding to integrated luminosities of 4.9 and 20.6 fb-1 of pp collisions collected at centre-of-mass energies (Formula presented.) TeV and 8 TeV, respectively. Signal candidates are identified through (Formula presented.) and (Formula presented.) decays. With a two-dimensional likelihood fit involving the (Formula presented.) reconstructed invariant mass and an angle between the (Formula presented.) candidate momenta in the muon pair rest frame, the yields of (Formula presented.) and (Formula presented.), and the transverse polarisation fraction in (Formula presented.) decay are measured. The transverse polarisation fraction is determined to be (Formula presented.) = 0.38 0.23 0.07(Formula presented.), and the derived ratio of the branching fractions of the two modes is (Formula presented.), where the first error is statistical and the second is systematic. Finally, a sample of (Formula presented.) decays is used to derive the ratios of branching fractions (Formula presented.) and (Formula presented.) = 10.4 3.1 1.5 0.6(Formula presented.), where the third error corresponds to the uncertainty of the branching fraction of (Formula presented.) decay. The available theoretical predictions are generally consistent with the measurement. © 2015, CERN for the benefit of the ATLAS collaboration.

Study of the Planacon XP85012 photomultiplier characteristics for its use in a Cherenkov detector / Karavicheva,TL / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

Main properties of the multi-anode microchannel plate photomultiplier to be used in a Cherenkov detector are discussed. The laboratory test results obtained using irradiation of the MCP-PMT photocathode by picosecond optical laser pulses with different intensities (from single photon regime to the PMT saturation conditions) are presented.

Study of Z boson production in pPb collisions at √sNN=5.02 TeV / Khachatryan,V. / Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 2016.

Annotation:

The production of Z bosons in pPb collisions at sNN=5.02 TeV is studied by the CMS experiment via the electron and muon decay channels. The inclusive cross section is compared to pp collision predictions, and found to scale with the number of elementary nucleon-nucleon collisions. The differential cross sections as a function of the Z boson rapidity and transverse momentum are measured. Though they are found to be consistent within uncertainty with theoretical predictions both with and without nuclear effects, the forward-backward asymmetry suggests the presence of nuclear effects at large rapidities. These results provide new data for constraining nuclear parton distribution functions. © 2016 The Author.

Surface layer structure of AISI 1020 steel at different stages of dry sliding under electric current of high density / Aleutdinov,KA / INTERNATIONAL CONFERENCE ON ADVANCED MATERIALS AND NEW TECHNOLOGIES IN MODERN MATERIALS SCIENCE 2015. - 2016.

Annotation:

Wear intensity of the sliding electric contact steel 1020/steel 1045 depending on sliding time is presented at the contact current density higher than 100 A/cm(2) without lubricant. It is shown that wear intensity of 1020 steel decreases at increasing of sliding time. Wear intensity is stabilized after some sliding time. This time (burn-in time) decreases at reduction of current density. Structural changes are realized in surface layer. Signs of liquid phase are observed on sliding surface. This liquid isn't a result of melting. It is established using Auger spectrometry that the contact layer contains up to 50 at.% of oxygen.

Surface modification of ferritic steels using MEVVA and duoplasmatron ion sources / Chalyhk,B.B. / Review of Scientific Instruments. - 2016.

Annotation:

Metal Vapor Vacuum Arc (MEVVA) ion source (IS) is a unique tool for production of high intensity metal ion beam that can be used for material surface modification. From the other hand, the duoplasmatron ion source provides the high intensity gas ion beams. The MEVVA and duoplasmatron IS developed in Institute for Theoretical and Experimental Physics were used for the reactor steel surface modification experiments. Response of ferritic-martensitic steel specimens on titanium and nitrogen ions implantation and consequent vacuum annealing was investigated. Increase in microhardness of near surface region of irradiated specimens was observed. Local chemical analysis shows atom mixing and redistribution in the implanted layer followed with formation of ultrafine precipitates after annealing. © 2015 AIP Publishing LLC.

Technological challenges at ITER plasma facing components production in Russia / Mazul,I.V. [и др.] // Fusion Engineering and Design. - 2016.

Annotation:

Major part of ITER plasma facing components will be manufactured in the Russian Federation (RF). Operational conditions and other requirements to these components, as well as the scale of production, are quite unique. These unique features and related technological solutions found in the frame of the project are discussed. Procedure breakdown and results of qualification for the proposed technologies and potential producers are presented, based on mockups production and testing. Design of qualification mockups and prototypes, testing programs and results are described. Basic quantitative and qualitative parameters of manufactured components and methods of quality control are presented. Critical manufacturing issues and prospects for unique production for future fusion needs are discussed. © 2016 Elsevier B.V.

Termosyphon cryogenic system for RED-100 detector / Sosnovtsev,V / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

A cryogenic system based on a two-phase closed tubular thermosyphon with 12 mm diameter copper tube is developed. It was used for thermal stabilization of the liquid xenon emission detector RED-100. The nitrogen refrigerant cooled down with a free-boiling liquid nitrogen bath has been used. It was shown that the system supports the RED100 operation at temperature 166 K with accuracy +/- 1K.

Test of the electric charge conservation law with Borexino detector / Vishneva,A / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

The new limit on the electron lifetime is obtained from data of the Borexino experiment. The expected signal from the e - gamma nu decay mode is a 256 keV photon detected in liquid scintillator. Because of the extremely low radioactive background level in the Borexino detector it was possible to improve the previous measurement by two orders of magnitude.

The Ce-144 source for SOX / Durero,M / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

The SOX (Short distance neutrino Oscillations with BoreXino) project aims at testing the light sterile neutrino hypothesis. To do so, two artificials sources of antineutrinos and neutrinos respectively will be consecutively deployed at the Laboratori Nazionali del Gran Sasso (LNGS) in close vicinity to Borexino, a large liquid scintillator detector. This document reports on the 0, source production and transportation. The source should exhibit a long lifetime and a high decay energy, a requirement fullfilled by the Ce-144-Pr-144 pair at secular equilibrium. It will be produced at FSUE "Mayak" PA using spent nuclear fuel. It will then be shielded and packed according to international regulation and shipped to LNGS across Europe. Knowledge of the Cerium antineutrino generator (CeANG) parameters is crucial for SOX as it can strongly impact the experiment sensitivity. Several apparatuses are being used or designed to characterize CeANG activity, radioactive emission and content. An overview of the measurements performed so far is presented here.

The central engine of GRB 130831A and the energy breakdown of a relativistic explosion / DePasquale,M / MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY. - 2016.

Annotation:

Gamma-ray bursts (GRBs) are the most luminous explosions in the Universe, yet the nature and physical properties of their energy sources are far from understood. Very important clues, however, can be inferred by studying the afterglows of these events. We present optical and X-ray observations of GRB 130831A obtained by Swift, Chandra, Skynet, Reionization And Transients Infra-Red camera, Maidanak, International Scientific Optical-Observation Network, Nordic Optical Telescope, Liverpool Telescope and Gran Telescopio Canarias. This burst shows a steep drop in the X-ray light curve at similar to 10(5) s after the trigger, with a power-law decay index of a similar to 6. Such a rare behaviour cannot be explained by the standard forward shock (FS) model and indicates that the emission, up to the fast decay at 105 s, must be of 'internal origin', produced by a dissipation process within an ultrarelativistic outflow. We propose that the source of such an outflow, which must produce the X-ray flux for similar to 1 d in the cosmological rest frame, is a newly born magnetar or black hole. After the drop, the faint X-ray afterglow continues with a much shallower decay. The optical emission, on the other hand, shows no break across the X-ray steep decrease, and the late-time decays of both the X-ray and optical are consistent. Using both the X-ray and optical data, we show that the emission after similar to 10(5) s can be explained well by the FS model. We model our data to derive the kinetic energy of the ejecta and thus measure the efficiency of the central engine of a GRB with emission of internal origin visible for a long time. Furthermore, we break down the energy budget of this GRB into the prompt emission, the late internal dissipation, the kinetic energy of the relativistic ejecta, and compare it with the energy of the associated supernova, SN 2013 fu.

The consequences of chronic radiation exposure of scots pine in the remote period after the chernobyl accident / Geras’kin,S.A. / Russian Journal of Ecology. - 2016.

Annotation:

Long-term observations on Scots pine populations (2003–2012) were performed in areas of Bryansk region radioactively contaminated by the Chernobyl fallout. Throughout the observation period, the frequency of cytogenetic alterations in the root meristem of germinated seeds of pine trees from radioactively contaminated test sites significantly exceeded the control level. Seeds developing under chronic radiation exposure were characterized by high interannual variation in viability. The quality of the seeds and their resistance to additional γ-irradiation showed no definite relationship with the level of radioactive contamination in the site and the radiation dose absorbed by the generative organs of Scots pine. © 2016, Pleiades Publishing, Ltd.

The DarkSide project / Agnes,P. / Journal of Instrumentation. - 2016.

Annotation:

DarkSide is a graded experimental project based on radiopure argon, and is now, and will be, used in direct dark matter searches. The present DarkSide-50 detector, operating at the Gran Sasso National Laboratory, is a dual-phase, 50 kg, liquid argon time-projection-chamber surrounded by an active liquid scintillator veto. It is designed to be background free in 3 years of operation. DS-50 performances, when filled with atmospheric argon, are reported. However DS-50 filled with underground argon, shows impressive reduction of the sup39/supAr isotope. The application of this powerful technology in a future generation of the DarkSide program is discussed. © 2016 IOP Publishing Ltd and Sissa Medialab srl.

The GAMMA-400 gamma-ray telescope for precision gamma-ray emission investigations / Topchiev,NP / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

The GAMMA-400 gamma-ray telescope with excellent angular and energy resolutions is designed to search for signatures of dark matter in the fluxes of gamma-ray emission and electrons + positrons. Precision investigations of gamma-ray emission from Galactic Center, Crab, Vela, Cygnus, Geminga, and other regions will be performed, as well as diffuse gamma-ray emission, along with measurements of high-energy electron + positron and nuclei fluxes. Furthermore, it will study gamma-ray bursts and gamma-ray emission from the Sun during periods of solar activity. The GAMMA-400 energy range is expected to be from similar to 20 MeV up to TeV energies for gamma rays, up to 10 TeV for electrons + positrons, and up to 10(15) eV for cosmic-ray nuclei. For 100-GeV gamma rays, the GAMMA-400 angular resolution is similar to 0.01 degrees and energy resolution is similar to 1%; the proton rejection factor is similar to 5x10(5). GAMMA-400 will be installed onboard the Russian space observatory.

The He-3 long-counter TETRA at the ALTO ISOL facility / Testov,D / NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT. - 2016.

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A new beta-decay station (BEDO) has been installed behind the PARRNe mass separator operated on-line at the electron-driven ALTO ISOL facility. The station is equipped with a movable tape collector allowing the creation of the radioactive sources of interest at the very center of a modular detection system. The mechanical structure was designed to host various assemblies of detectors in compact geometry. We report here the first on-line use of this system equipped with the 4 pi He-3 neutron counter TETRA built at JINR Dubna associated with HPGe and plastic 4 pi beta detectors. The single neutron detection efficiency achieved is 53(2)% measured using the Cf-252 source. For beta-delayed neutron measurements the neutron detection efficiency was derived from the comparison of gated gamma-spectra. The on-line commissioning of the TETRA setup was performed with laser-ionized gallium beams. 13 and neutron events were recorded as a function of time. From these data we report P-1n(Ga-82)=22(2)% and T-1/2(Ga-82)=0.604(11) s in good agreement with values available in the literature. The new detection system will be used in other experiments aimed at investigations of beta-decay properties of neutron-rich isotopes produced at ALTO. (C) 2016 Elsevier B.V. All rights reserved.

The high energy cosmic ray particle spectra measurements with the PAMELA calorimeter / Adriani,O. / Nuclear and Particle Physics Proceedings. - 2016.

Annotation:

Up until now there has been limited, contradictive data on the high energy range of the cosmic ray electron-positron, proton and helium spectra. Due to the limitations of the use of a magnetic spectrometer, over 8 years experimental data was processed using information from a sampling electro-magnetic calorimeter, a neutron detector and scintillator detectors. The use of these devices allowed us to successfully obtain the high energy cosmic ray particle spectra measurements. The results of this study clarify previous findings and greaten our understanding of the origin of cosmic rays. © 2015 Elsevier B.V.

The high precision measurement of the Ce-144 activity in the SOX experiment / DiNoto,L / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

In order to perform a resolutive measurement to clarify the neutrino anomalies and to observe possible short distance neutrino oscillations, the SOX (Short distance neutrino Oscillations with BoreXino) experiment is under construction. In the first phase, a 100 kCi Ce-144-Pr-144 antineutrino source will be placed under the Borexino detector at the Laboratori Nazionali del Gran Sasso (LNGS), in center of Italy, and the rate measurement of the antineutrino events, observed by the very low radioactive background Borexino detector, will be compared with the high precision ( 1%) activity measurement performed by two calorimeters. The source will be embedded in a 19 mm thick tungsten alloy shield and both the calorimeters have been conceived for measuring the thermal heat absorbed by a water flow. In this report the design of the calorimeters will be described in detail and very preliminary results will be also shown.

The May 17, 2012 solar event: back-tracing analysis and flux reconstruction with PAMELA / Bruno,A / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

The PAMELA space experiment is providing first direct observations of Solar Energetic Particles (SEPs) with energies from about 80 MeV to several GeV in near-Earth orbit, bridging the low energy measurements by other spacecrafts and the Ground Level Enhancement (GLE) data by the worldwide network of neutron monitors. Its unique observational capabilities include the possibility of measuring the flux angular distribution and thus investigating possible anisotropies associated to SEP events. The analysis is supported by an accurate back-tracing simulation based on a realistic description of the Earth's magnetosphere, which is exploited to estimate the SEP energy spectra as a function of the asymptotic direction of arrival with respect to the Interplanetary Magnetic Field (IMF). In this work we report the results for the May 17, 2012 event.

The measurement of the dipole anisotropy of protons and helium cosmic rays with the PAMELA experiment / Adriani,O / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

In the framework of the PAMELA experiment the features of the large-scale anisotropy have been measured within the energy range 1-20 TeV/n. The measurements were carried out with the use of the calorimeter on the base of the hypothesis about the existence of a dipole anisotropy. The amplitude and phase of the dipole were obtained. The results are in agreement with the ground-based observations.

The new experiment WAGASCI for water to hydrocarbon neutrino cross section measurement using the J-PARC beam / Bronner,C / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

The T2K (Tokai-to-Kamioka) is a long baseline neutrino experiment designed to study various parameters that rule neutrino oscillations, with an intense beam of muon neutrinos. A near detector complex (ND280) is used to constrain non-oscillated flux and hence to predict the expected number of events in the far detector (Super-Kamiokande). The difference in the target material between the far (water) and near (scintillator, hydrocarbon) detectors leads to the main non-canceling systematic uncertainty for the oscillation analysis. In order to reduce this uncertainty a new water grid and scintillator detector, WAGASCI, has been proposed. The detector will be operated at the J-PARC neutrino beam line with the main physics goal to measure the charged current neutrino cross section ratio between water and hydrocarbon with a few percent accuracy. Further physics program may include high-precision measurements of different charged current neutrino interaction channels. The concept of the new detector will be covered together with the actual construction plan.

The prospects of creation of well-type xenon gamma-ray spectrometer / Petrenko,D / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

Possibility of creation of a well-type gamma detector based on xenon gamma-ray spectrometer was shown. The results of modelling of xenon well-type detectors are presented.

The registration system of the coordinate-tracking setup on the drift chambers / Zadeba,EA / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

The large-scale coordinate-tracking detector for registration of near-horizontal muon flux generated by ultra-high energy cosmic rays is being developed in MEPhI. Detector is based on the multiwire drift chambers from the neutrino experiment at the IHEP U-70 accelerator. Their key advantages are a large effective area (1.85 m(2)), good coordinate and angular resolution with a small number of measuring channels. Detector will be operated as a part of the experimental complex NEVOD, in particular, its registration system allows joint operation with Cherenkov water detector (CWD) and coordinate detector DECOR. Coordinate tracking unit on the drift chambers (CTUDC) is mounted on the opposite sides of CWD. It consists of two coordinate planes containing 8 drift chambers and represents a prototype of a full-size setup. Registration system of the CTUDC is based on the E-MISS electronics developed in IHEP, its principle of operation is presented.

The scientific data acquisition system of the GAMMA-400 space project / Bobkov,SG / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

The description of scientific data acquisition system (SDAS) designed by SRISA for the GAMMA-400 space project is presented. We consider the problem of different level electronics unification: the set of reliable fault-tolerant integrated circuits fabricated on Silicon-on-Insulator 0.25 mkm CMOS technology and the high-speed interfaces and reliable modules used in the space instruments. The characteristics of reliable fault-tolerant very large scale integration (VLSI) technology designed by SRISA for the developing of computation systems for space applications are considered. The scalable net structure of SDAS based on Serial RapidIO interface including real-time operating system BAGET is described too.

The software and hardware for the ground testing of ALFA-ELECTRON space spectrometer / Batischev,AG / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

The complex for ground testing and space detector system calibration has been designed. The fast multilayer scintillation detector of the new telescope-spectrometer for the ALFA-ELECTRON space experiment is in ground testing mode now. The device will planned to install on the outer surface of the Russian Segment of the International Space Station. The basic scheme for the detector amplitude parameters measurement by use of specially designed hardware and software are described and the first prototype testing results are demonstrated.

The structure of control and data transfer management system for the GAMMA-400 scientific complex / Bobkov,SG / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

A description of the control and data transfer management system for scientific instrumentation involved in the GAMMA-400 space project is given. The technical capabilities of all specialized equipment to provide the functioning of the scientific instrumentation and satellite support systems are unified in a single structure. Control of the scientific instruments is maintained using one-time pulse radio commands, as well as program commands in the form of 16-bit code words, which are transmitted via onboard control system and scientific data acquisition system. Up to 100 GByte of data per day can be transferred to the ground segment of the project. The correctness of the proposed and implemented structure, engineering solutions and electronic elemental base selection has been verified by the experimental working-off of the prototype of the GAMMA-400 scientific complex in laboratory conditions.

The study of rare earth production based on processing of phosphorus-containing concentrates / Bujnovskij,A.S. / Key Engineering Materials. - 2016.

Annotation:

Due to their unique properties, rare-earth elements (REEs) are used in many areas of advanced high-tech industries. One of the most important sources of REEs is phosphoruscontaining ores and concentrates, in particular monazite and apatite concentrates. Although a number of monazite processing methods are commercially used, they have some limitations. That is why the extensive research efforts are underway to develop new methods for recovery of REEs from monazite. This paper presents the research results for nitric-acid pressure decomposition of phosphorus-containing concentrate from the unique man-made deposit and demonstrates that this method is feasible in principle. © Copyright 2016 Trans Tech Publications Ltd, Switzerland.

The Taiga project / Boreyko,V / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

The TAIGA project is aimed at solving the fundamental problems of gamma-ray astronomy and physics of ultrahigh energy cosmic rays with the help of the complex of detectors, located in the Tunka valley (Siberia, Russia). TAIGA includes a wide-angle large area Tunka-HiSCORE array, designed to detect gamma-rays of ultrahigh energies in the range 20-1000 TeV and charged cosmic rays with energies of 100 TeV-100 PeV, large area muon detector to improve the rejection of background EAS protons and nuclei and a network of imaging atmospheric Cherenkov telescopes for gamma radiation detection. We discuss the goals and objectives of the complex features of each detector and the results obtained in the first stage of the HiSCORE installation.

The transverse momentum dependence of charged kaon Bose-Einstein correlations in the SELEX experiment / Akgun,U. / Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 2016.

Annotation:

We report the measurement of the one-dimensional charged kaon correlation functions using 600GeV/c σsup-/sup, πsup-/sup and 540GeV/c p beams from the SELEX (E781) experiment at the Fermilab Tevatron. Ksup±/supKsup±/sup correlation functions are studied for three transverse pair momentum, kT, ranges and parameterized by a Gaussian form. The emission source radii, R, and the correlation strength, λ, are extracted. The analysis shows a decrease of the source radii with increasing kaon transverse pair momentum for all beam types. © 2015 The Authors.

The veto system of the DarkSide-50 experiment / Agnes,P. / Journal of Instrumentation. - 2016.

Annotation:

Nuclear recoil events produced by neutron scatters form one of the most important classes of background in WIMP direct detection experiments, as they may produce nuclear recoils that look exactly like WIMP interactions. In DarkSide-50, we both actively suppress and measure the rate of neutron-induced background events using our neutron veto, composed of a boron-loaded liquid scintillator detector within a water Cherenkov detector. This paper is devoted to the description of the neutron veto system of DarkSide-50, including the detector structure, the fundamentals of event reconstruction and data analysis, and basic performance parameters. © 2016 IOP Publishing Ltd and Sissa Medialab srl.

Thermal conductivity of perspective fuel based on uranium nitride / Solntceva,E.S. / Annals of Nuclear Energy. - 2016.

Annotation:

The comparative analysis of the results obtained by the authors of this paper and the available literature data on the thermal conductivity of uranium mononitride was prepared, analytical review of the thermal properties of mixed uranium-plutonium nitride fuel also was done. The analysis has shown that characteristics such as porosity and amount of impurities (which are determined by fuel fabrication technology) have a significant influence on thermal conductivity of the nitride fuel. Thermal conductivity of mixed uranium-plutonium fuel, in addition, is very sensitive to the content of PuN. The data obtained agree well with those taken from literature sources, and can be reliably described using known correlations. Correlations of thermal conductivity on temperature, porosity and impurity content, presented in this study, can be used to predict fuel behavior. © 2014 Published by Elsevier Ltd.

Thermal neutrons registration by xenon gamma-ray detector / Shustov,AE / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

Experimental results of thermal neutrons detection by high pressure xenon gamma-ray spectrometers are presented. The study was performed with two devices with sensitive volumes of 0.2 and 2 litters filled with compressed mixture of xenon and hydrogen without neutron-capture additives. Spectra from Pu-Be neutron source were acquired using both detectors. Count rates of the most intensive prompt neutron-capture gamma-ray lines of xenon isotopes were calculated in order to estimate thermal neutrons efficiency registration for each spectrometer.

Thermal stability of the microstructure of 12% chromium ferritic–martensitic steels after long-term aging at high temperatures / Mozhanov,E.M. / Technical Physics. - 2016.

Annotation:

The structure of EK-181 (RUSFER-EK-181, low-activation) and ChS-139 12% Cr ferritic–martensitic steels is investigated and their mechanical properties are tested after long-term (13500 h) aging at 450 and 620°C. The microstructure of the steels exhibits a high thermal stability, which provides the retention of their initial short-term mechanical properties at test temperatures. © 2016, Pleiades Publishing, Ltd.

To the question of learnability of a spiking neuron with spike-timing-dependent plasticity in case of complex input signals / Serenko,A. / Advances in Intelligent Systems and Computing. - 2016.

Annotation:

Results of investigations of learnability of a spiking neuron in case of complex input signals which encode binary vectors are presented. The disadvantages of the supervised learning protocol with stimulating the neuron by current impulses in desired moments of time are analyzed. © Springer International Publishing Switzerland 2016.

Tracking performance of GasPixel detectors in test beam studies / Boldyrev,A.S. / Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment. - 2016.

Annotation:

A combination of a pixel chip and a gas chamber (GasPixel detectors) opens new opportunities for particle detectors. GasPixel detectors consist of an electron drift volume, an amplification gap and an anode plane based on a semiconductor chip. This technology promises large benefits in high-energy charged-particle tracking. It allows reconstruction of a 3D image of a particle track segment in a single detector layer with high accuracy. Several prototypes of GasPixel detectors based on micromegas technology with different gas mixtures and drift gaps were studied in a test beam. A spatial resolution of 8 μm and angular accuracy of about 0.2° in a chip plane were obtained. A dedicated Monte Carlo simulation of GasPixel detectors shows good agreement with experimental data. © 2015 Elsevier B.V. All rights reserved.

Transverse momentum dependence of D-meson production in Pb-Pb collisions at √ssubNN/sub = 2.76 TeV / TheALICEcollaboration / Journal of High Energy Physics. - 2016.

Annotation:

The production of prompt charmed mesons Dsup0/sup, Dsup+/sup and Dsup∗+/sup, and their antiparticles, was measured with the ALICE detector in Pb-Pb collisions at the centre-of-mass energy per nucleon pair, (Formula presented.) , of 2.76 TeV. The production yields for rapidity |y| < 0.5 are presented as a function of transverse momentum, pT, in the interval 1–36 GeV/c for the centrality class 0–10% and in the interval 1–16 GeV/c for the centrality class 30–50%. The nuclear modification factor RAA was computed using a proton-proton reference at (Formula presented.) TeV, based on measurements at (Formula presented.) TeV and on theoretical calculations. A maximum suppression by a factor of 5-6 with respect to binary-scaled pp yields is observed for the most central collisions at pT of about 10 GeV/c. A suppression by a factor of about 2-3 persists at the highest pT covered by the measurements. At low pT (1-3 GeV/c), the RAA has large uncertainties that span the range 0.35 (factor of about 3 suppression) to 1 (no suppression). In all pT intervals, the RAA is larger in the 30-50% centrality class compared to central collisions. The D-meson RAA is also compared with that of charged pions and, at large pT, charged hadrons, and with model calculations. © 2016, The Author(s).

Transverse momentum spectra of inclusive b jets in pPb collisions at √sNN=5.02 TeV / Khachatryan,V. / Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 2016.

Annotation:

We present a measurement of b jet transverse momentum (pT) spectra in proton-lead (pPb) collisions using a dataset corresponding to about 35 nbsup-1/sup collected with the CMS detector at the LHC. Jets from b quark fragmentation are found by exploiting the long lifetime of hadrons containing a b quark through tagging methods using distributions of the secondary vertex mass and displacement. Extracted cross sections for b jets are scaled by the effective number of nucleon-nucleon collisions and are compared to a reference obtained from pythia simulations of pp collisions. The pythia-based estimate of the nuclear modification factor is found to be 1.22±0.15(stat+syst pPb)±0.27(syst pythia) averaged over all jets with pT between 55 and 400 GeV/c and with |ηlab|<2. We also compare this result to predictions from models using perturbative calculations in quantum chromodynamics. © 2016 CERN for the benefit of the CMS Collaboration.

Trapped positrons observed by PAMELA experiment / Adriani,O / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

Measurements of electron and positron spatial distributions in energy range from 80 MeV to several GeV below the geomagnetic cutoff rigidity were carried out using the PAMELA magnetic spectrometer. The instrument is installed on board the Resurs-DK satellite which was launched June 15th 2006 on an elliptical orbit with the inclination 70 degrees and the altitude 350-600 km. The procedure of trajectories calculations in the geomagnetic filed gives a way to separate stably trapped and short lived albedo components produced in interactions of cosmic ray protons with the residual atmosphere. The work presents spatial distributions of trapped, quasitrapped and short-lived albedo electrons and positrons in the near Earth space. Electron to positron ratio points out on different production mechanism of trapped and quasitrapped particles.

Z (+)(4430): Nonexotic interpretation / Uglov,TV, Pakhlov,PN / PHYSICS OF ATOMIC NUCLEI. - 2016.

Annotation:

The possibility of describing the charged charmonium-like state Z (+)(4430) as the kinematical rescattering effect is examined. This approach makes it possible to avoid the introduction of exotic hadron states in the model, and one describes structures in the psi(2S)pi(+) mass spectrum by the presence of the D (s) ((*)') resonance in a hidden intermediate state. The resulting model predictions are compared with the results obtained by the LHCb Collaboration.

Understanding the detector behavior through Montecarlo and calibration studies in view of the SOX measurement / Caminata,A / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

Borexino is an unsegmented neutrino detector operating at LNGS in central Italy. The experiment has shown its performances through its unprecedented accomplishments in the solar and geoneutrino detection. These performances make it an ideal tool to accomplish a state-of-the-art experiment able to test the existence of sterile neutrinos (SOX experiment). For both the solar and the SOX analysis, a good understanding of the detector response is fundamental. Consequently, calibration campaigns with radioactive sources have been performed over the years. The calibration data are of extreme importance to develop an accurate Monte Carlo code. This code is used in all the neutrino analyses. The Borexino-SOX calibration techniques and program and the advances on the detector simulation code in view of the start of the SOX data taking are presented.

Unified model of primordial black holes and dark matter formation / Grobov,AV / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

We propose a unified model of primordial black holes and soliton dark matter formation. Dynamic of spherically symmetric clumps of scalar field is considered in Newtonian approximation. The formation of hidden mass of the Universe is discussed. Numerical solution of the system of interacting scalar and gravitational fields is used to obtain the mass of a clumps.

Upper bound on neutrino mass based on T2K neutrino timing measurements / Abe,K. / Physical Review D - Particles, Fields, Gravitation and Cosmology. - 2016.

Annotation:

The Tokai to Kamioka (T2K) long-baseline neutrino experiment consists of a muon neutrino beam, produced at the J-PARC accelerator, a near detector complex and a large 295-km-distant far detector. The present work utilizes the T2K event timing measurements at the near and far detectors to study neutrino time of flight as a function of derived neutrino energy. Under the assumption of a relativistic relation between energy and time of flight, constraints on the neutrino rest mass can be derived. The sub-GeV neutrino beam in conjunction with timing precision of order tens of ns provide sensitivity to neutrino mass in the few MeV/c2 range. We study the distribution of relative arrival times of muon and electron neutrino candidate events at the T2K far detector as a function of neutrino energy. The 90% C.L. upper limit on the mixture of neutrino mass eigenstates represented in the data sample is found to be mν2<5.6 MeV2/c4. © 2016 American Physical Society.

Use of tungsten single crystals to enhance nuclear reactors structural elements properties / Solntceva,E.S. / International Journal of Hydrogen Energy. - 2016.

Annotation:

This paper demonstrates advantages of using tungsten single crystal as structural material in science absorbing industry in comparison with polycrystalline material. High-temperature short-term static strength and creep resistance characteristics of polycrystalline tungsten and single crystal alloy were obtained and compared. The results of comparative studies of the mechanical properties of polycrystalline and monocrystalline tungsten - 4% tantalum alloy are presented.It is shown that monocrystalline tungsten based materials have both high-temperature strength and plasticity which makes them most suitable for use under high temperatures and high mechanical stresses. Use of monocrystalline tungsten as a structural material makes it possible to prolong the service life and avoid the failures resulting from embrittlement and strain. Moreover, thermo mechanical treatment of monocrystalline tungsten enhances its high-temperature strength. However, it is necessary to carry out additional experimental research to choose the appropriate thermo mechanical treatment conditions. © 2016 Hydrogen Energy Publications, LLC.

Visualization tool for X-ray scanner for sTGC detector production quality control / Konovalov,SP / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

The ATLAS experiment at the Large Hadron Collider has an ambitious program of the detector upgrade to meet an expected rise of accelerator luminosity. The first large system which supposed to be installed in 2019 is the New Small Wheel (NSW) for ATLAS muon spectrometer. In order to ensure high quality and reliability of NSW chambers an X-ray scanning technique is being developed. One of the main components of the X-ray scanner is a special software visualization tool which would allow a fast and clear representation of scanning results and an identification of possible chamber defects.

Testing composite parametrical hypotheses without applying the reduction / Vlasova,S, Vlasov,V, Tolokonsky,A / IX INTERNATIONAL CONFERENCE ON MODERN TECHNIQUES OF PLASMA DIAGNOSTICS AND THEIR APPLICATION. - 2016.

Annotation:

Usually when the parametrical hypotheses are being tested the Wald reduction from composite hypothesis to the simple one is used. However, in order to apply the reduction method it is needed to know the distribution law of unknown parameter. Practically such a law cannot be determined precisely using the experimental data. First of all, it requires long supervision over the controlled stationary process to provide an inalterability of probability characteristics of the process. In practice the modifications in technological process could be made, and therefore the probability characteristics of the process can also change. Using the example of exponential distribution the algorithm of testing composite parametrical hypothesis about the distribution parameter which does not exceed the declared threshold value without use of reduction is considered in article. Such approach is based on the fact that the partition boundary of the sample space depends monotonously on unknown value of the interest parameter.

The method for measuring of the characteristics of the cosmic ray dipole anisotropy in the PAMELA experiment / Voronov,SA, Karelin,AV / XVI WORKSHOP ON HIGH ENERGY SPIN PHYSICS (D-SPIN2015). - 2016.

Annotation:

The large-scale cosmic ray anisotropy has been studied in the equatorial coordinate system in the PAMELA experiment. The method to obtain dipole anisotropy characteristics as well as some its modernizations is discussed in detail.

Looking for chiral anomaly in K gamma - K pi reactions / Vysotsky,MI, Zhemchugov,EV / PHYSICAL REVIEW D. - 2016.

Annotation:

In an experiment currently being performed at the Institute for High Energy Physics, Serpukhov, Russia, a beam of charged kaons is directed on a copper target. In the electromagnetic field of the target nuclei, two reactions occur: K+gamma - K+pi(0) and K+gamma - K-0 pi(+). A peculiar distinction between these two reactions is that there is a chiral anomaly contribution in the former reaction, but not in the latter. This contribution can be directly seen through comparison of the cross sections of these reactions near the threshold. We derive expressions for these cross sections taking into account the anomaly and the contribution of the lightest vector mesons.

Worker Radiation Exposure / Tsov'yanov,AG / ATOMIC ENERGY. - 2016.

Annotation:

This article contains information on professional external and internal radiation exposure in 2013 of workers in organizations, including NPP, on territories serviced by the Federal Medical-Biological Agency of Russia (FMBA). The parameters of the dose distribution are calculated: mode, median, average, standard deviation, quantile, and coeffi cient of variation for institutions on territories serviced by the FMBA. The number of individuals subject to individual dosimetric monitoring, grouped by institution and taking account of the radiation exposure dose is analyzed. Information on the professional external and internal radiation exposure of NPP workers is presented.

Xenon gamma-ray spectrometer for radioactive waste controlling complex / Ulin,S / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

Xenon detector based gamma-ray spectrometer for a radioactive waste sorting complex and its characteristics are described. It has been shown that the "thin-wall" modification of the detector allows better registration of low-energy gamma rays (tens of keV). The spectrometer is capable of operation in unfavorable field conditions and can identify radionuclides of interest in less than 1 second.

New engineering decisions in nuclear engineering / Yablonovsky,I.M., Fedorenko,D.N., Kravchenko,P.D. / ARPN Journal of Engineering and Applied Sciences. - 2016.

Annotation:

The paper has presented options of the security system when demounting the radioactive equipment of nuclear power stations, design options for the transport-hoisting equipment demounting, constructive schemes of the fuel-handling machine with the flexible suspension of the overloading object and the automatic device of the turn and capture of a pressure pen case fuse in the Water-Cooled Type Reactor. © 2006-2016 Asian Research Publishing Network (ARPN). All rights reserved.

Yields of p, d, t formed in stopped pion absorption by intranuclear clusters / Chernyshev,BA / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

Results of the study of spectra and yields of p, d, t formed in stopped pion absorption by nuclei are presented. Data on charged particle formation have been obtained for 17 isotopes in wide atomic mass range (6 A 209). Empirical model was proposed to describe A-dependences of primary p, d, t yields.

Gravitational lensing and polarization in astrophysics / Zakharov,AlexanderF / XVI WORKSHOP ON HIGH ENERGY SPIN PHYSICS (D-SPIN2015). - 2016.

Annotation:

We discuss astrophysical problems connected with gravitational lensing where current and future polarimetric observations are very important to clarify theoretical models. Namely, we consider polarization observations for exoplanet searches with gravitational microlensing, optical polarization for gravitational lens systems, polarization signatures of cosmological gravitational waves.

Study of spatial and energy characteristics of relativistic electron bursts in magnetosphere with robust methods / Zharaspayev,TR, Aleksandrin,SYu, Koldashov,SV / INTERNATIONAL CONFERENCE ON PARTICLE PHYSICS AND ASTROPHYSICS (ICPPA-2015). - 2016.

Annotation:

Electron bursts are well-known phenomena of fast increase in particle fluxes in near-Earth space. Powerful local geophysical events like earthquakes or thunderstorms can induce precipitation of electrons with defined energy spectrum from the radiation belt, which would be registered as fast increase in particle count rate on board the low orbit satellite. Using particle burst energy spectrum evolution in time one can detect the area of particles precipitation. Background particles are registered by instruments too and can't be separated from burst particles. High level of background particles can have large impact on detection of the area of particles precipitation. A robust regression method to solve problem of background particles is introduced and compared with standard method of linear regression. Results of comparison between various data analysis methods in application to study of spatial and energy characteristics of relativistic electron bursts in the Earth magnetosphere are presented in this work. Robust method proved to be optimal for data analysis of energy spectrum evolution in time for search of zones of local radiation belt disturbances.

Defining quantitative criteria for the physical protection system effectiveness of nuclear facilities / Zhukov,A., Geraskin,N., Krasnoborodko,A. // Defense and Security Analysis. - 2016.

Annotation:

The article is devoted to problems of defining quantitative criteria for the physical protection system (PPS) effectiveness of nuclear facilities. The article briefly describes the scheme of the PPS development used in the nuclear industry in Russia, gives a review of existing approaches to defining the minimal acceptable value of the system's effectiveness, and reveals advantages and disadvantages of the approaches. The article describes in detail an approach based on facility categorization by potential losses and a technique of defining the minimal acceptable value of the PPS effectiveness developed on its base. © 2016 Taylor & Francis

2015
A coordinate-tracking setup based on drift chambers for investigating ultrahigh energy cosmic rays / Zadeba,E.A. / Bulletin of the Russian Academy of Sciences: Physics. - 2015

Annotation:

A large-scale coordinate-tracking setup for registering the near-horizontal muon flux from ultrahigh energy cosmic rays is under development at the MEPhI. The setup is based on drift chambers from the neutrino detector at the Institute of High Energy Physics’ U-70 accelerator, which have a large sensitive area (1.85 msup2/sup) and good angular and spatial resolution with a relatively low number of measuring channels. © 2015, Allerton Press, Inc.

A drift detector system with anode and cathode readout in the GlueX experiment / Pentchev,L. / Instruments and Experimental Techniques. - 2015

Annotation:

A drift detector system designed to detect charged particle tracks in the GlueX experiment dedicated to study the nature of confinement is described. The key design features of the drift chambers associated with the requirement of a minimum material budget in the path of secondary particles are presented. The spatial resolution and the detection efficiency have been measured with cosmic rays using the automatic data acquisition system.

A first search for cosmogenic neutrinos with the ARIANNA Hexagonal Radio Array / Barwick,S.W. / Astroparticle Physics. - 2015

Annotation:

The ARIANNA experiment seeks to observe the diffuse flux of neutrinos in the 10sup8/sup-10sup10/sup GeV energy range using a grid of radio detectors at the surface of the Ross Ice Shelf of Antarctica. The detector measures the coherent Cherenkov radiation produced at radio frequencies, from about 100 MHz-1 GHz, by charged particle showers generated by neutrino interactions in the ice. The ARIANNA Hexagonal Radio Array (HRA) is being constructed as a prototype for the full array. During the 2013-14 austral summer, three HRA stations collected radio data which was wirelessly transmitted off site in nearly real-time. The performance of these stations is described and a simple analysis to search for neutrino signals is presented. The analysis employs a set of three cuts that reject background triggers while preserving 90% of simulated cosmogenic neutrino triggers. No neutrino candidates are found in the data and a model-independent 90% confidence level Neyman upper limit is placed on the all flavor ν+ν¯ flux in a sliding decade-wide energy bin. The limit reaches a minimum of 1.9×10sup-23/supGeV-sup1/supcm-sup2/sups-sup1/supsr-sup1/sup in the 10sup8.5/sup-10sup9.5/sup GeV energy bin. Simulations of the performance of the full detector are also described. The sensitivity of the full ARIANNA experiment is presented and compared with current neutrino flux models. © 2015 Elsevier B.V.

A measurement of the neutron lifetime using the method of storage of ultracold neutrons and detection of inelastically up-scattered neutrons / Arzumanov,S. / Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 2015.

Annotation:

We present estimations of systematic corrections and results of their experimental studies for our neutron lifetime experiment carried out in 2008-2010 at ILL. Taking into account these systematic corrections, we reduce the data of three independent sets of measurements (obtained during period 2008-2010) performed with different energy spectra of ultracold neutrons (UCNs) at different trap temperatures to the mean neutron lifetime value equal to 880.2(1.2) s. © 2015 The Authors.

A novel insight on the geometry of plasma channels of nanosecond micron-size discharges on the surface of living tissues of plants / Zuimatch,E.A./ Plasma Processes and Polymers. - 2015

Annotation:

This paper describes the chip that is used for generating nanosecond surface micron-size discharges, as well as the results of observations of their interaction with surfaces of living tissues of plants: onion shell, leaves of Canada water weed, and day nettle petals. The interaction was observed for the first time in cellular size range. It was identified that the trajectories of plasma discharge channels follow intercellular walls and have a zigzag shape. It was also identified that a single discharge having <0.5 mJ energy results in destruction of cell wall, which stimulates intensive juice excretion. A chip for generating nanosecond surface micron-size discharges is described. Results of observations of their interaction with surfaces of living tissues of plants are presented. It is found that the trajectories of plasma channels follow intercellular walls and have a zigzag shape. It is also identified that a single discharge results in destruction of cell wall, which stimulates juice excretion. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

A quantitative method of text emotiveness evaluation on base of the psycholinguistic markers founded on morphological features / Gudovskikh,D / 4TH INTERNATIONAL YOUNG SCIENTIST CONFERENCE ON COMPUTATIONAL SCIENCE. - 2015.

Annotation:

A new quantitative approach to identifying emotionally colored texts that reflect the excited state of its authors is proposed. This approach uses special psycholinguistic markers of text based on morphological characters ratios of Russian language. To apply such markers the morphological parser in combination with an ensemble of SVM classifiers was developed. Testing results of selected topics texts are presented. The study was conducted using texts from different sources such as news, regular blogs, microblogs, social network posts. It showed that results of developed approach can be a useful extension of Big Data methods of traditional sentiment analysis and it can be applicable to developing methods of personality computing.

A scintillator based endcap K-L and muon detector for the Belle II experiment / Aushev,T / NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT. - 2015.

Annotation:

A new K-L(0) and muon detector based on scintillators will be used for the endcap regions in the Belle II experiment, currently under construction. The increased luminosity of the e(+)e(-) SuperKEKB collider entails challenging detector requirements. We demonstrate that relatively inexpensive polystyrene scintillator strips with wavelength shifting fibers ensure a sufficient light yield at the Silicon PhotoMultiplier (SiPM) photodetector, are robust and provide improved physics performance for the Belle II experiment compared to its predecessor, Belle. (C) 2015 Elsevier B.V. All rights reserved

A search for high-mass resonances decaying to tau(+)tau(-) in pp collisions at root s=8 TeV with the ATLAS detector / Aad,G / JOURNAL OF HIGH ENERGY PHYSICS. - 2015

Annotation:

A search for high-mass resonances decaying into tau(+)tau(-) final states using proton-proton collisions at root s = 8 TeV produced by the Large Hadron Collider is presented. The data were recorded with the ATLAS detector and correspond to an integrated luminosity of 19.5-20.3 fb(-1). No statistically significant excess above the Standard Model expectation is observed; 95% credibility upper limits are set on the cross section times branching fraction of Z' resonances decaying into tau(+)tau(-) pairs as a function of the resonance mass. As a result, Z' bosons of the Sequential Standard Model with masses less than 2.02 TeV are excluded at 95% credibility. The impact of the fermionic couplings on the Z' acceptance is investigated and limits are also placed on a Z' model that exhibits enhanced couplings to third-generation fermions.

A search for t(t)over-bar resonances using lepton-plus-jets events in proton-proton collisions at root s=8 TeV with the ATLAS detector / Aad,G / JOURNAL OF HIGH ENERGY PHYSICS. - 2015

Annotation:

A search for new particles that decay into top quark pairs is reported. The search is performed with the ATLAS experiment at the LHC using an integrated luminosity of 20.3 fb(-1) of proton-proton collision data collected at a centre-of-mass energy of root s = 8TeV. The lepton-plus-jets final state is used, where the top pair decays to W (+) bW(-)(b) over bar, with one W boson decaying leptonically and the other hadronically. The invariant mass spectrum of top quark pairs is examined for local excesses or deficits that are inconsistent with the Standard Model predictions. No evidence for a top quark pair resonance is found, and 95% confidence-level limits on the production rate are determined for massive states in benchmark models. The upper limits on the cross-section times branching ratio of a narrow Z' boson decaying to top pairs range from 4.2 pb to 0.03 pb for resonance masses from 0.4 TeV to 3.0 TeV. A narrow leptophobic topcolour Z' boson with mass below 1.8 TeV is excluded. Upper limits are set on the cross-section times branching ratio for a broad colour-octet resonance with Gamma/m = 15% decaying to tt. These range from 4.8 pb to 0.03 pb for masses from 0.4 TeV to 3.0 TeV. A Kaluza-Klein excitation of the gluon in a Randall-Sundrum model is excluded for masses below 2.2 TeV.

A two-phase emission liquid Xe detector for study of low-ionization events at the research reactor IRT MEPhI / Akimov,D.Y. / IEEE Transactions on Nuclear Science. - 2015.

Annotation:

A two-phase emission detector containing 5 kg of liquid Xe is installed at the horizontal experimental channel of the research nuclear reactor IRT MEPhI to measure the liquid Xe response to nuclei recoils with kinetic energies below 1 keV. Preliminary tests have demonstrated that ≥ 15 μs electron lifetime in liquid Xe and ~ 10 photoelectrons single ionization electron signal are achieved. These parameters are sufficient to detect and identify events at the single electron level.

A г probe for radionuclide diagnostics of cancer / Zhukov,K.I. / Instruments and Experimental Techniques. - 2015.

Annotation:

A miniature γ probe for nuclear medicine based on a LaBr3:Ce scintillation crystal and a silicon photomultiplier is described. The γ ray detection efficiency is 29% for 137Cs (662 keV) and 70% for 57Co (122 keV). The spatial resolution and selectivity measured with a tungsten collimator for 57Co are 8 mm and 26°, respectively.

ALFA-ELECTRON Experiment Onboard the International Space Station / Batischev,A.G. / Physics Procedia. - 2015.

Annotation:

The fast multilayered scintillation detector (MSD) of the new telescope-spectrometer for the space experiment ALFA-ELECTRON planned to work on the outer surface of the Russian Segment (RS) of the International Space Station (ISS) is presented. The MSD spectrometer can measure an intensive flow (up to 10 MHz or higher) of electrons with energies of from 2 up to 20 MeV and their short-term variations (up to 1 ms). An apparatus physical characteristics and operation of the MSD are described. The results of the detector investigations in the mode of high intensities are demonstrated also. © 2015 The Authors.

Amplitude analysis of e(+)e(-) - Upsilon(nS)pi(+)pi(-) at root s=10.866 GeV / Garmash,A / PHYSICAL REVIEW D. - 2015.

Annotation:

We report results on studies of the e(+)e(-) annihilation into three-body Upsilon(nS)pi(+)pi(-) (n = 1, 2, 3) final states including measurements of cross sections and the full amplitude analysis. The cross sections measured at root s = 10.866 GeV and corrected for the initial state radiation are sigma(e(+)e(-) -- Upsilon(1S)pi(+)pi(-)) = (2.27 +/- 0.12 +/- 0.14) pb, sigma(e(+)e(-) -- Upsilon(2S)pi(+)pi(-)) = (4.07 +/- 0.16 +/- 0.45) pb, and sigma(e(+)e(-) -- Upsilon(3S)pi(+)pi(-)) = (1.46 +/- 0.09 +/- 0.16) pb. Amplitude analysis of the three-body Upsilon(nS)pi(+)pi(-) final states strongly favors I-G(J(P)) = 1(+)(1(+)) quantum-number assignments for the two bottomonium-like Z(b)(+/-) states, recently observed in the Upsilon(nS)pi(+) and h(b)(mP)pi(+)(m = 1, 2) decay channels. The results are obtained with a 121.4 fb(-1) data sample collected with the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider.

Amplitude and timing properties of a Geiger discharge in a SiPM cell / Vinogradov,S. / Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment. - 2015.

Annotation:

The amplitude and timing properties of a Geiger discharge in a stand-alone SiPM cell have been investigated in detail. Use of a single stand-alone SiPM cell allows us to perform measurements with better accuracy than the multicell structure of conventional SiPMs. We have studied the dependence of the output charge and amplitude from an SiPM cell illuminated by focused light vs the number of primary photoelectrons. We propose a SPICE model which explains the amplitude over saturation (when the SiPM's amplitude is greater than the sum over all cells) characteristics of SiPM signals for more than one initial photoelectrons. The time resolutions of a SiPM cell have been measured for the case of single (SPTR) and multiphoton light pulses. The Full Width Half Max (FWHM) for SPTR has been found to be at the level of 30. ps for focused and 40. ps for unfocused light (100. ?m cell size).

An Algorithm of Finding Thematically Similar Documents with Creating Context-semantic Graph Based on Probabilistic-entropy Approach / Moloshnikov,I.A. / Procedia Computer Science. - 2015.

Annotation:

An algorithm of finding documents on a given topic based on a selected reference collection of documents along with creating context-semantic graph for visualizing themes in search results is presented. The algorithm is based on integration of set of probabilistic, entropic, and semantic markers for extractions of weighted key words and combinations of words, which describe the given topic. Test results demonstrate an average precision of 99% and the recall of 84% on expert selection of documents. Also developed special approach to constructing graph on base of algorithms that extract key phrases with weights. It gives the possibility to demonstrate a structure of subtopics in large collections of documents in compact graph form. © 2015 The Authors.

Analysis of events with b-jets and a pair of leptons of the same charge in pp collisions at √s=8 TeV with the ATLAS detector / TheATLAScollaboration / Journal of High Energy Physics. - 2015.

Annotation:

An analysis is presented of events containing jets including at least one b-tagged jet, sizeable missing transverse momentum, and at least two leptons including a pair of the same electric charge, with the scalar sum of the jet and lepton transverse momenta being large. A data sample with an integrated luminosity of 20.3 fbsup−1/sup of pp collisions at √s = 8 TeV recorded by the ATLAS detector at the Large Hadron Collider is used. Standard Model processes rarely produce these final states, but there are several models of physics beyond the Standard Model that predict an enhanced rate of production of such events; the ones considered here are production of vector-like quarks, enhanced four-top-quark production, pair production of chiral b′-quarks, and production of two positively charged top quarks. Eleven signal regions are defined; subsets of these regions are combined when searching for each class of models. In the three signal regions primarily sensitive to positively charged top quark pair production, the data yield is consistent with the background expectation. There are more data events than expected from background in the set of eight signal regions defined for searching for vector-like quarks and chiral b′-quarks, but the significance of the discrepancy is less than two standard deviations. The discrepancy reaches 2.5 standard deviations in the set of five signal regions defined for searching for four-top-quark production. The results are used to set 95% CL limits on various models. © 2015, The Author(s).

ANALYSIS, COLLIGATION, AND INVESTIGATION OF THE THERMAL CONDUCTIVITY OF FUEL COMPOSITIONS BASED ON URANIUM MONONITRIDE / Vybyvanets,VI / ATOMIC ENERGY. - 2015.

Annotation:

The aims of this work were to compare the results of studies performed by the present authors using the existing data on the thermal conductivity of uranium mononitride and colligate and analyze the thermal conductivity of mixed uranium-plutonium fuel. The dependence of the thermal conductivity on the content of impurities and the porosity of a material was investigated. It was shown that there is a discrepancy in the experimental data. Since it determines the presence of impurities and porosity, the technology used to fabricate the fuel has a considerable effect on the change in the thermal conductivity.

Analyzing the temperature effect of high mountain cosmic ray detectors using the database of the global network of muon telescopes / Osipenko,A.S. / Bulletin of the Russian Academy of Sciences: Physics. - 2015.

Annotation:

The temperature effect of high mountain muon detectors, which exceeds the theoretically expected one, is investigated. The inverse instrument problem for experimental determination of the density of the temperature coefficient is solved. Results provided by the mddb database created for muon detectors are used as observational data and briefly described. © 2015, Allerton Press, Inc.

Angular asymmetries as a probe for anomalous contributions to HZZ vertex at the LHC / Konoplich,R / PHYSICAL REVIEW D. - 2015.

Annotation:

In this article, the prospects for studying the tensor structure of the HZZ vertex with the LHC experiments are presented. The structure of tensor couplings in Higgs di-boson decays is investigated by measuring the asymmetries and by studying the shapes of the final state angular distributions. The expected background contributions, detector resolution, and trigger and selection efficiencies are taken into account. The potential of the LHC experiments to discover sizeable non-Standard Model contributions to the HZZ vertex with 300 and 3000 fb(-1) is demonstrated.

Angular coefficients of Z bosons produced in pp collisions at s=8 TeV and decaying to μsup+/supμsup-/sup as a function of transverse momentum and rapidity / Khachatryan,V. / Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 2015.

Annotation:

Measurements of the five most significant angular coefficients, Ainf0/inf through Ainf4/inf, for Z bosons produced in pp collisions at s=8 TeV and decaying to μsup+/supμsup-/sup are presented as a function of the transverse momentum and rapidity of the Z boson. The integrated luminosity of the dataset collected with the CMS detector at the LHC corresponds to 19.7fbsup-1/sup. These measurements provide comprehensive information about the Z boson production mechanisms, and are compared to the QCD predictions at leading order, next-to-leading order, and next-to-next-to-leading order in perturbation theory. © 2015 CERN for the benefit of the CMS Collaboration.

Antakov,M.A. New Class of Pseudo-Random Hexagonal Configurations for Coding Collimators of Ionizing Radiation / Antakov,M.A., Tereshchenko,S.A., Fedorov,G.A. / Biomedical Engineering. - 2015.

Annotation:

New ways of constructing two-dimensional hexagonal configurations based on pseudo-random and extended pseudo-random sequences are presented. The first method involves adding or subtracting elements of traditional hexagonal configuration. Pseudo-rectangular hexagonal configurations with hexagonal cells and their modifications were obtained. All configurations keep their periodicity and ability for mosaic construction allowing using them for creation of multi-pinhole coding collimators for registration of ionizing radiation. © 2015 Springer Science+Business Media New York

Antarctic radio frequency albedo and implications for cosmic ray reconstruction / Stockham,J. / Radio Science. - 2015.

Annotation:

We describe herein a measurement of the Antarctic surface "roughness" performed by the balloon-borne ANITA (Antarctic Impulsive Transient Antenna) experiment. Originally purposed for cosmic ray astrophysics, the radio frequency (RF) receiver ANITA gondola, from its 38 km altitude vantage point, can scan a disk of snow surface 600 km in radius. The primary purpose of ANITA is to detect RF emissions from cosmic rays incident on Antarctica, such as neutrinos which penetrate through the atmosphere and interact within the ice, resulting in signal directed upward which then refracts at the ice-air interface and up and out to ANITA, or high-energy nuclei (most likely irons or protons), which interact in the upper atmosphere (at altitudes below ANITA) and produce a spray of down-coming RF which reflects off the snow surface and back up to the gondola. The energy of such high-energy nuclei can be inferred from the observed reflected signal only if the surface reflectivity is known. We describe herein an attempt to quantify the Antarctic surface reflectivity, using the Sun as a constant, unpolarized RF source. We find that the reflectivity of the surface generally follows the expectations from the Fresnel equations, lending support to the use of those equations to give an overall correction factor to calculate cosmic ray energies for all locations in Antarctica. The analysis described below is based on ANITA-II data. After launching from McMurdo Station in December 2008, ANITA-II was aloft for a period of 31 days with a typical instantaneous duty cycle exceeding 95%.

Application of physical-empirical models to calculate a fragment of the phase diagram and the physical properties of BCC Fe–Cr alloys: I. Formulation of a model and the estimation and approximation of experimental data / Udovskii,A.L., Vasil’ev,D.A. / Russian Metallurgy (Metally). - 2015.

Annotation:

An approach, which includes the application of physical-empirical models for describing the contributions to the Gibbs energy of mixing of solid solutions for binary systems, is formulated. The chemical contribution at zero temperature is represented as the difference between the chemical energy of mixing obtained by ab inito calculations and the elastic contribution of the energy of lattice distortions that is caused by the size factor, which takes into account the matrix atom displacements in the first-third coordination spheres with respect to impurity atoms. The vibrational contribution to the Gibbs energy of a solid solution is considered using the Debye model with allowance for anharmonicity in the Mie–Grüneisen approximation, the magnetic contribution to the Gibbs energy is considered using the Inden–Hillert–Jarl formalism, and the contribution of thermally excited electrons is considered using electronic specific heat. The experimental data on the Debye temperature, the Curie temperature, the average magnetic moment, Young’s modulus, the thermal expansion coefficient, and the electronic specific heat of ferromagnetic bcc Fe–Cr solid solutions are analyzed, and the approximation of these properties depending on the alloy composition is considered. The effect of temperature on the dimension factor is © 2015, Pleiades Publishing, Ltd.

Application of the URAGAN muon hodoscope to calibrate charged particle detectors / Ampilogov,N.V. / Bulletin of the Russian Academy of Sciences: Physics. - 2015.

Annotation:

Independent calibration of the charged particle detectors is often required in developing different devices for elementary particle physics. The use of the URAGAN muon hodoscope, created at MEPhI’s NEVOD Scientific and Educational Center, is described. The high accuracy of muon track reconstruction allows calibration and precision study of the sensitive working volume of such detectors. © 2015, Allerton Press, Inc.

Application of video-assisted tactile sensor and finite element simulation for estimating young's modulus of porcine liver / Dosaev,M. / Journal of Medical and Biological Engineering. - 2015.

Annotation:

Surgeons use palpation for tasks such as the identification of biological tissues and the localization of blood vessels and boundaries of local inclusions. Human tissues are unavailable for palpation during laparoscopic operations. A device that can help surgeons distinguish different soft tissues is thus desirable. This study proposes an approach for palpation that uses a self-developed video-assisted tactile sensor. The sensing device, which consists of a video camera, a force sensor, and a semispherical head made of polydimethylsiloxane, can measure the contact area and load on an object. A numerical simulation of the indentation process was performed based on the finite element method. The bisection method was used to estimate the Young's modulus of the object by fitting the results of the simulation to the experimental contact area and load. Fresh porcine livers were used to represent soft tissues to verify the approach. Force control was used in the tests and calculations. The average Young's modulus of the fresh porcine livers was 1.1 kPa. To simulate altered tissue, the porcine liver was boiled. The results showed that the modulus of the boiled livers was 25 times higher than that of the fresh porcine livers. Therefore, the proposed approach can distinguish normal tissue from altered tissue, and is thus feasible for palpation. © Taiwanese Society of Biomedical Engineering 2015.

Application prospects of multilayer film shields for space equipment protection against constant magnetic fields / Grabchikov,S.S. / Bulletin of the Lebedev Physics Institute. - 2015.

Annotation:

Protection of scientific equipment aboard spacecrafts against both natural and artificial constant magnetic fields is an urgent problem. Multilayer film electromagnetic shields produced by electrodeposition showed high shielding efficiency during laboratory tests. To test their application prospects under conditions of real space flights, a “Nanomag” scintillation telescope was developed and fabricated. Laboratory tests which demonstrated its operability at magnetic field induction to 4 mT are presented in this paper. © 2015, Allerton Press, Inc.

Application Prospects of Multilayer Film Shields for Space Research Instrumentation / Nyunt,P.W. / Physics Procedia. - 2015.

Annotation:

We have studied the magnetic properties of multilayer film cylindrical configuration shields (MFS) based on NiFe / Cu. The studied samples were prepared by electrode position. MFS were constituted by alternating layers of NiFe and Cu, deposited on an aluminum cylinder with diameter of 4 cm, length of 13 cm and 0.5 cm thickness. The thickness of each ferromagnetic layer varied from 10 to 150 μm, and the thickness of Cu layers was 5 μm. Five-samples in which the number of ferromagnetic layers varied from 3 to 45 and copper - from 2 to 44 were tested. The best shielding efficiency was achieved at the maximum number of layers and comprised about 102. Permalloy multilayer foil shield at the same total thickness has several times less efficiency in comparison with MFS. The description of a prototype of the charged particles telescope for space application is presented. Results of its testing regarding sensitivity to the constant magnetic field are described. © 2015 The Authors.

Arkhangelskaja,I.V. GRBs Redshift Distribution Shape Properties as Confirmation of their Progenitors Population Non-uniformity / Arkhangelskaja,I.V. / Physics Procedia. - 2015.

Annotation:

In the supposition of sources population uniformity the GRBs redshift distribution shape could similar ones for other objects with demonstrated or theoretically required uniform space allocation. The shape of redshift distribution for uniform sources set in our Metagalaxy defined by properties of space and cosmological parameters. Supernovae of Ia type were considered as populations with real uniform distributions on redshift because of it were used for definition of Ω and Λ or our Metagalaxy. Therefore, the GRB sources redshift distribution analysis allows us to investigate the uniformity of this population. The results of redshifts distribution investigation for GRB with defined duration from Swift/BAT registered subset (308 events) are discussed. The analysis of Swift/BAT GRBs subset duration distribution allows to conclude the difference of boundary between short and long events from value of 2 s obtained from CGRO/BATSE bursts catalogue. Durations of 1 s and 0.6 s more likely correspond to this separator point for Swift/BAT GRBs subset duration distributions without and with correction on redshift. Two long GRBs with known redshift subsets were analysed: one contains the events registered from the beginning of Swift/BAT operation up to the end of autumn, 2014 (273 bursts) and other was similar but up to the end of August, 2015 (284 events). The shapes of these distributions sufficiently differ from ones for SN Ia supernovae. Also the sufficient deficit of GRB with z2 was found during both subsets analysis. Moreover, this feature existence retain in the same redshift region even if the bursts with sources redshift defined using one of the methods (for example, afterglow absorption lines studying) included in the analysable subset. Such deficit was not observed in QSO redshift distribution and thereof it couldn't explained as apparatus effects caused by some difficulties to measure z because of the lack of strong emission or absorption lines covered by optical spectrometers if object located at high z values. The occurrence of minimum in long GRBs redshift distribution allows to conclude non-uniformity of its progenitors population and existence at least two subclasses in long GRB class. The obtained results allow considering that the whole GRB subset with known redshifts usage as "standard candles" for various cosmological tests could be excluded. Before such analysis different GRB samples might be separated and then various subsets could be investigated separately just as short and long events. © 2015 The Authors.

Arkhangelskaja,I.V. Redshift distribution of gamma-ray bursts: Evidence for the long GRBs sources population nonuniformity / Arkhangelskaja,I.V. / Bulletin of the Russian Academy of Sciences: Physics. - 2015.

Annotation:

The results of redshifts distribution investigation for 275 γ-ray bursts (GRBs) with defined duration from the Swift experiment catalogue are discussed. Detailed investigation of the redshift distribution shows that the former has at least two maxima at the 95% significance level in contradiction with the similar distribution for uniform samples in our Metagalaxy. This pattern (demonstrating the nonuniformity of the long GRB sources population) persists even if short GRBs with durations of t90 < 2 s without redshift correction, which corresponds to the classical definition of short GRB events, are excluded from consideration and if the analysis uses any sample of a smaller size for previous years. Preliminary investigation of the GRBs distribution on redshift and duration also reveals another subgroup that can be interpreted as intermediate GRB events. This subgroup persists if the analysis is confined to the distribution of those GRBs whose redshifts z are determined using one method only, e.g., from analyzing afterglow absorption lines. © 2015, Allerton Press, Inc.

Arkhangelskaja,I.V. The Properties of the Gamma-ray Bursts with High-energy Spectral Component / Arkhangelskaja,I.V. / Physics Procedia. - 2015.

Annotation:

Spectral properties of some GRB with presence of high-energy component are discussed. The energy spectra shape of GRBs with high energy emission presence can follows the Band model (or power law or broken power law) up to some tens or hundreds of MeV (as for GRB 100724B and GRB 021008) or contains additional high energy power law component (for example, GRB 050525B and GRB 090902B). Both GRBs types were registered since CGRO mission has begun. The analysis of their energy spectra has shown that the break between low energy spectral part (described by either Band or power law or broken power law etc. models) and additional component was in energy region 2 - 200 MeV. The Fermi/LAT low energy threshold is lower than CGRO/BATSE one and the very low-energy spectral component described by power law with index δ and characterised X-ray emission in the range E50 keV was introduced for several bursts energy spectra approximation. Moreover, for several GRBs this spectral parameter δ similar to Γ (characterizing gamma-emission in the band E 100 MeV) and the question about formation of wide range emission during GRB due to single mechanism arises again. © 2015 The Authors.

Arkhangelskiy,A.I. The Application of Digital Techniques for Spectrometric Apparatus in Space Research / Arkhangelskiy,A.I., Glyanenko,A.S., Arkhangelskaja,I.V. / Physics Procedia. - 2015

Annotation:

The application of digital methods for spectrometric observations by example of space projects executing at MEPhI is described. Some aspects of using schematic solutions and electronic component base are discussed. The example of realisation of space born spectrometer is presented. © 2015 The Authors.

Array of scintillation detectors for the MONICA spectrometer / Kvashnin,A.A. / Bulletin of the Lebedev Physics Institute. - 2015.

Annotation:

An array of scintillation detectors of the MONICA Spectrometer, whis is aimed at investigating fluxes of cosmic-ray ions (from H to Ni) in the extraterrestrial space within the energy range from 10 to 300 MeV per nucleon, is considered. The basic goal of the MONICA experiment is the measurement of the ionic and isotopic composition of cosmic rays of the galactic and solar origin, as well as the measurement of their energy spectrum. This problem was intensely studied by numerous investigators [1–10]; nevertheless, a lot of questions remain unsolved up to now, in this field of science. The array of scintillation detectors plays the important role in achieving the goals of the MONICA experiment. The composition of the array, tuning procedure, and characteristics of scintillation detectors are discussed in detail. © 2015, Allerton Press, Inc.

Astrakhantsev,NYu Many-body effects in graphene beyond the Dirac model with Coulomb interaction / Astrakhantsev,NYu, Katsnelson,MI, Braguta,VV / PHYSICAL REVIEW B. - 2015.

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This paper is devoted to the development of perturbation theory for studying the properties of graphene sheets of finite size, at nonzero temperature and chemical potential. The perturbation theory is based on the tight-binding Hamiltonian and arbitrary interaction potential between electrons, which is considered as a perturbation. One-loop corrections to the electron propagator and to the interaction potential at nonzero temperature and chemical potential are calculated. One-loop formulas for the energy spectrum of electrons in graphene, for the renormalized Fermi velocity and also for the dielectric permittivity, are derived.

ATLAS Run 1 searches for direct pair production of third-generation squarks at the Large Hadron Collider / Aad,G. / European Physical Journal C. - 2015.

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This paper reviews and extends searches for the direct pair production of the scalar supersymmetric partners of the top and bottom quarks in proton–proton collisions collected by the ATLAS collaboration during the LHC Run 1. Most of the analyses use 20 fbsup-1/sup of collisions at a centre-of-mass energy of √s = 8 TeV, although in some case an additional 4.7 fb-1 of collision data at √s = 7 TeV are used. New analyses are introduced to improve the sensitivity to specific regions of the model parameter space. Since no evidence of third-generation squarks is found, exclusion limits are derived by combining several analyses and are presented in both a simplified model framework, assuming simple decay chains, as well as within the context of more elaborate phenomenological supersymmetric models. © 2015, CERN for the benefit of the ATLAS collaboration.

Azimuthal Anisotropy in U plus U and Au plus Au Collisions at RHIC / Adamczyk,L / PHYSICAL REVIEW LETTERS. - 2015.

Annotation:

Collisions between prolate uranium nuclei are used to study how particle production and azimuthal anisotropies depend on initial geometry in heavy-ion collisions. We report the two- and four-particle cumulants, v(2)2 and v(2)4, for charged hadrons from U + U collisions at root s(NN) = 193 GeV and Au + Au collisions at root s(NN) = 200 GeV. Nearly fully overlapping collisions are selected based on the energy deposited by spectators in zero degree calorimeters (ZDCs). Within this sample, the observed dependence of v(2)2 on multiplicity demonstrates that ZDC information combined with multiplicity can preferentially select different overlap configurations in U + U collisions. We also show that v(2) vs multiplicity can be better described by models, such as gluon saturation or quark participant models, that eliminate the dependence of the multiplicity on the number of binary nucleon-nucleon collisions.

Background Conditions for the October 29, 2003 Solar Flare by the AVS-F Apparatus Data / Troitskaya,E.V. / Physics Procedia. - 2015.

Annotation:

The background model for AVS-F apparatus onboard CORONAS-F satellite for the October 29, 2003 X10-class solar flare is discussed in the presented work. This background model developed for AVS-F counts rate in the low- and high-energy spectral ranges in both individual channels and summarized. Count rate were approximated by polynomials of high order taking into account the mean count rate in the geomagnetic equatorial region at the different orbits parts and Kp-index averaged on 5 bins in time interval from -24 to -12 hours before the time of geomagnetic equator passing. The observed averaged counts rate on equator in the region of geomagnetic latitude ±5o and estimated minimum count rate values are in coincidence within statistical errors for all selected orbits parts used for background modeling. This model will used to refine the estimated energy of registered during the solar flare spectral features and detailed analysis of their temporal profiles behavior both in corresponding energy bands and in summarized energy range. © 2015 The Authors.

Bakaldin,A.V. Earth magnetic field as analyzer of the cosmic ray ion charge in MONICA experiment / Bakaldin,A.V., Voronov,S.A. / Journal of Physics: Conference Series. - 2015.

Annotation:

The future onboard experiment MONICA (monitor of cosmic ray nuclei and ions) is aimed for studying the cosmic ray ion fluxes from H to Ni in the energy range 10-300 MeV/n in vicinity of Earth. It's main scientific objective is the measurement of ion ionization states, as well as elemental, isotope composition and energy spectra of Solar Energetic Particle (SEP) fluxes. The method of the ion ionization state measurement based on the usage of Earth magnetic field as a separator of particle charge will be utilized in this experiment. The present contribution is dedicated to investigate the possibilities and features of this method for the MONICA experiment. The real time dependences of inverse square of cut-off geomagnetic L-shell (LinfC/inf; sup-2/sup) on magnetic rigidity (R) in rigidity range 640-2780 MV were studied experimentally during powerful SEP events December 13-15 2006. The possibility to simulate these dependences using the modern geomagnetic field models is analyzed as well. © Published under licence by IOP Publishing Ltd.

Barminova,H.Y. Modeling of intense charged particle bunch dynamics in external magnetic fields / Barminova,H.Y., Saratovskyh,M.S. / Journal of Physics: Conference Series. - 2015.

Annotation:

Program module CAMFT is developed to simulate the intense charged particle bunch dynamics in external magnetic fields. The program is based on the accurate solution of the motion equation for each particle of the intense bunch. The program is written on C++ language and uses standart OpenMP (version 2.0) for parallelization, so one can simulate the behavior of the bunch with intensity about 10sup9/sup-10sup10/sup particles. Visual C++ and library Qt 4.8.3 of qtcreator are used for the result visualization. Dynamics of the bunch with arbitrary phase distributions in magnetic fields of arbitrary geometry may be studied by means of the program. The actual CAMFT version is checked while simulating the accelerating structure with racetrack geometry. Modified CAMFT version is checked for ITEP Heavy-Ion Prototype charge-state separator. © Published under licence by IOP Publishing Ltd.

Barothermography and microstructure of the hypoeutectic and eutectic alloys in Al–Si system / Dediaeva,E. / Journal of Thermal Analysis and Calorimetry. - 2015.

Annotation:

Differential barothermal analysis (DBA or HP-DTA) of the phase transformations in hypoeutectic Al-10 at.% Si and eutectic Al-12 at.% Si alloys was carried out at 100 MPa of argon pressure and at temperatures up to 700 °C. Liquidus temperature of Al-10 at.% Si is reduced during melting and crystallization by 3–4 °C as compared with the atmospheric pressure data. Increase in the eutectic transformation L → (Al) + Si temperature up to 580–581 °C during heating was found for the Al-10 at.% Si and Al-12 at.% Si alloys. According to the barothermography data, a slight thermal effect at 553 °C is detected for both alloys, which was identified as the decomposition of aluminum-based solid solution and precipitation of silicon particles. The improvement of silicon phase morphology for Al-10 at.% Si and Al-12 at.% Si alloys after hot isostatic pressing (HIP) at the pressure of 100 MPa and temperature of 550 °C was found. No porosity in the alloy has been established after HIP treatment. After HIP thermal expansion, coefficients of the alloy are noticeably decreased by 25 (Al-10 at.% Si) and 50 % (Al-12 at.% Si). © 2015 Akadémiai Kiadó, Budapest, Hungary

Beam-energy-dependent two-pion interferometry and the freeze-out eccentricity of pions measured in heavy ion collisions at the STAR detector / Adamczyk,L. / Physical Review C - Nuclear Physics. - 2015.

Annotation:

We present results of analyses of two-pion interferometry in Au+Au collisions at sNN=7.7, 11.5, 19.6, 27, 39, 62.4, and 200 GeV measured in the STAR detector as part of the BNL Relativistic Heavy Ion Collider Beam Energy Scan program. The extracted correlation lengths (Hanbury-Brown-Twiss radii) are studied as a function of beam energy, azimuthal angle relative to the reaction plane, centrality, and transverse mass (mT) of the particles. The azimuthal analysis allows extraction of the eccentricity of the entire fireball at kinetic freeze-out. The energy dependence of this observable is expected to be sensitive to changes in the equation of state. A new global fit method is studied as an alternate method to directly measure the parameters in the azimuthal analysis. The eccentricity shows a monotonic decrease with beam energy that is qualitatively consistent with the trend from all model predictions and quantitatively consistent with a hadronic transport model. © 2015 American Physical Society.

Belotsky,K.M. On Recombination of Dark Matter Particles with Dark U(1) Interaction / Belotsky,K.M., Esipova,E.A., Kirillov,A.A. / Physics Procedia. - 2015.

Annotation:

This work is devoted to consideration of recombination effects of long-range interacting dark matter. It includes some calculation details and discussion of questions which remained outside the scope of arXiv:1506.03094. © 2015 The Authors.

Belotsky,KM Clusters of primordial black holes and reionization problem / Belotsky,KM, Kirillov,AA, Rubin,SG / PHYSICS OF ATOMIC NUCLEI. - 2015.

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Clusters of primordial black holes may cause the formation of quasars in the early Universe. In turn, radiation from these quasars may lead to the reionization of the Universe. However, the evaporation of primordial black holes via Hawking's mechanism may also contribute to the ionization of matter. The possibility of matter ionization via the evaporation of primordial black holes with allowance for existing constraints on their density is discussed. The contribution to ionization from the evaporation of primordial black holes characterized by their preset mass spectrum can roughly be estimated at about 10(-3).

Belotsky,KM Primordial black holes and the observable features of the universe / Belotsky,KM, Kirillov,AA, Rubin,SG / INTERNATIONAL JOURNAL OF MODERN PHYSICS D. - 2015.

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Here, we briefly discuss the possibility to solve simultaneously with primordial black holes (PBHs) the problems of dark matter (DM), reionization of the universe, origin of positron line from Galactic center and supermassive black hole (BH) in it. Discussed scenario can naturally lead to a multiple-peak broad-mass-range distribution of PBHs in mass, which is necessary for simultaneous solution of the problems.

Belotsky,KM Primordial black holes with mass 10(16)-10(17) g and reionization of the Universe / Belotsky,KM, Kirillov,AA / JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS. - 2015

Annotation:

Primordial black holes (PBHs) with mass 10(16) - 10(17) g almost escape constraints from observations so could essentially contribute to dark matter density. Hawking evaporation of such PBHs produces with a steady rate gamma- and e(+/-)-radiations in MeV energy range, which can be absorbed by ordinary Simplified estimates show that a small fraction of evaporated energy had to be absorbed by baryonic matter what can turn out to be enough to heat the matter so it is fully ionized at the redshift z similar to 5...10. The result is found to be close to a borderline case where the effect appears, what makes it sensitive to the approximation used. In our approximation, degree of gas ionization reaches 50-100% by z similar to 5 for PBH mass (3...7) x 10(16) g with their abundance corresponding to the upper limit.

Belousova,D.B. Evaluation of reliability of a perforated pipe when working in the stream of liquid metal coolant / Belousova,D.B., Samokhin,D.S. / IOP Conference Series: Materials Science and Engineering. - 2015.

Annotation:

The article describes the approach to the assessment of indicators of reliability of products, having in its composition of perforated pipes. The idea of writing this article was born during the practical work on the reliability of the mass transfer performance evaluation system, which is part of the system to maintain the concentration of oxygen in a systems perspective SVBR-100. The article provides an overview of the currently existing, approaches to estimate the reliability of the products containing a perforated structure, as well as theoretical and practical part, to the use of the proposed approach. © Published under licence by IOP Publishing Ltd.

Belyaev,N.L. Study of the CP-violating effects with gg → Η → τsup+/supτsup–/sup process / Belyaev,N.L., Konoplich,R.V. / Physics of Atomic Nuclei. - 2015.

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Study of the gg → Η → τsup+/supτsup–/sup process was performed at Monte Carlo level within the framework of searching for CP-violating effects. The sensitivity of chosen observables to CP-parity of the Higgs boson was demonstrated for hadronic 1-prong τ decays (τsup±/sup → πsup±/sup, ρsup±/sup). Monte Carlo samples for the gg → Η → τsup+/supτsup-/sup process were generated including the parton hadronisation to final state particles. This generation was performed for the Standard Model Higgs boson, the pseudoscalar Higgs boson, the Z → τsup+/supτsup–/sup background, and mixed CP-states of the Higgs boson. © 2015, Pleiades Publishing, Ltd.

Big Data Processing in the ATLAS Experiment: Use Cases and Experience / De,Kaushik / 4TH INTERNATIONAL YOUNG SCIENTIST CONFERENCE ON COMPUTATIONAL SCIENCE. - 2015.

Annotation:

The physics goals of the next Large Hadron Collider run include high precision tests of the Standard Model and searches for new physics. These goals require detailed comparison of data with computational models simulating the expected data behavior. To highlight the role which modeling and simulation plays in future scientific discovery, we report on use cases and experience with a unified system built to process both real and simulated data of growing volume and variety.

Binding energy of the X(3872) at unphysical pion masses / Baru,V / PHYSICAL REVIEW D. - 2015.

Annotation:

The chiral extrapolation of the X(3872) binding energy is investigated using the modified Weinberg formulation of chiral effective field theory for the D (D) over bar* scattering. Given its explicit renormalizability, this approach is particularly useful to explore the interplay of the long-and short-range D (D) over bar* forces in the X(3872) from studying the light-quark (pion) mass dependence of its binding energy. In particular, the parameter-free leading-order calculation shows that the X pole disappears for unphysically large pion masses. On the other hand, without contradicting the naive dimensional analysis, the higher-order pion-mass-dependent contact interaction can change the slope of the binding energy at the physical point, yielding the opposite scenario of a more strongly bound X at pion masses larger than its physical value. An important role of the pion dynamics and of the three-body D (D) over bar pi effects for chiral extrapolations of the X pole is emphasized. The results of the present study should be of practical value for lattice simulations since they provide a nontrivial connection between lattice points at unphysical pion masses and the physical world.

Bishler,L. Evolution method and HOMFLY polynomials for virtual knots / Bishler,L., Morozov,A., Morozov,A. / International Journal of Modern Physics A. - 2015.

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Following the suggestion of Alexei Morozov, Andrey Morozov and Anton Morozov, Phys. Lett. B737, 48(2014), arXiv:1407.6319, to lift the knot polynomials for virtual knots and links from Jones to HOMFLY, we apply the evolution method to calculate them for an infinite series of twist-like virtual knots and antiparallel two-strand links. Within this family one can check topological invariance and understand how differential hierarchy is modified in virtual case. This opens a way towards a definition of colored (not only cabled) knot polynomials, though problems still persist beyond the first symmetric representation. © 2015 World Scientific Publishing Company.

Blaschke,D Robustness of the baryon-stopping signal for the onset of deconfinement in relativistic heavy-ion collisions / Blaschke,D, Ivanov,YuB / PHYSICAL REVIEW C. - 2015.

Annotation:

The impact of the experimental acceptance, i.e. transverse-momentum (p(T)) cutoff and limited rapidity region, on the earlier predicted irregularity in the excitation function of the baryon stopping is studied. This irregularity is a consequence of the onset of deconfinement occurring in the compression stage of a nuclear collision and manifests itself as a wiggle in the excitation function of the reduced curvature (C-y) of the net-proton rapidity distribution at midrapidity. It is demonstrated that the wiggle is a very robust signal of a first-order phase transition that survives even under conditions of a very limited acceptance. At the same time the C-y for pure hadronic and crossover transition scenarios become hardly distinguishable, if the acceptance cuts off too much of the low-p(T) proton spectrum and/or puts a rapidity window that is too narrow around midrapidity. It is found that the shape of the net-proton rapidity distribution near midrapidity depends on the p(T) cutoff. This implies that the measurements should be taken at the same acceptance for all collision energies in order to reliably conclude the presence or absence of the irregularity.

Bolozdynya,A.I. Experiments on Direct Dark Matter Search with Two-phase Emission Detectors / Bolozdynya,A.I. / Physics Procedia. - 2015.

Annotation:

Emission detectors, invented 45 years ago in MEPhI, found their unique application in modern experiments searching for cold dark matter in the form of weakly ionizing massive particles (WIMPs). The current best limits for the interaction cross sections of supersymmetric WIMPs having a mass of 100 GeV/c2 with nucleons were measured with emission detector LUX containing 360 kg of liquid xenon as detector medium installed in Davis' cave at Homestake mine in South Dakota. Emission detectors of the next generation G2, with an active detector mass of about 10 tons, will either unambiguously detect WIMPs or rule out all current theoretical predictions for WIMP existence. Detectors of the G3 generation will be used for multiple purposes including detection of double beta neutrinoless decay and low-energy neutrinos. © 2015 The Authors.

Brazing of hexagonal boron-nitride ceramics with VT1-0 titanium alloy using a rapidly quenched titanium-based brazing alloy / Fedotov,I.V. / Welding International. - 2015.

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A brazing alloy was developed for the brazing of boron-nitride ceramics with VT1-0 alloy in the form of nanostructured rapidly quenched tapes. The wetting capacity of the boron-nitride ceramics by the brazing alloys of the Ti-Zr system is evaluated. The surface of the brazing alloy tape was investigated by X-ray diffraction and topographic methods and the brazed joints between theVT1-0 titanium alloy and boron-nitride ceramics were studied by examination of microstructure and mechanical properties. © 2014 © 2014 Taylor & Francis.

Calculation of the Covariation Matrix of the Neutron Flux Density in the Multigroup Diffusion Model of a Subcritical Reactor / Cherezov,AL / ATOMIC ENERGY. - 2015.

Annotation:

The reconstruction of fields and adjustment of the parameters of reactor models are increasingly prioritized for reactor physics because the efficiency and safety of the control of a nuclear plant depend on solving them. The results of reconstruction and parameter adjustments are largely determined by the probability distributions of the computed and measured data. The probability distribution of the computed data in turn depends on the properties of the neutron-physical model and probabilistic characteristics of the parameters of this model. The present work is devoted to the search for and investigations of efficient algorithms for calculating the covariation functions of the neutron flux density. A model of a stationary subcritical reactor with an internal neutron source is studied. Linear perturbation theory, the theorem on the spectral decomposition of operators, and the theory of stochastic processes are the tools used for performing the analysis.

Calibration Telescope System of CWD NEVOD as a Detector of Electron and Muon Components of EAS / Amelchakov,M.B./ Physics Procedia. - 2015.

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The paper describes the system of calibration telescopes as a part of the experimental complex NEVOD. The setup operation parameters were analysed during experimental series from 01/06/2013 to 21/01/2015. The technique of the charged particle local density spectrum reconstruction is described. The results of the local density spectrum measurements are presented for the EAS electron and muon components in different energy ranges of primary cosmic rays. © 2015 The Authors.

Centrality and rapidity dependence of inclusive jet production in sNN=5.02 TeV proton-lead collisions with the ATLAS detector / Abbott,B. / Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 2015.

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Measurements of the centrality and rapidity dependence of inclusive jet production in sNN=5.02 TeV proton-lead (p+Pb) collisions and the jet cross-section in s=2.76 TeV proton-proton collisions are presented. These quantities are measured in datasets corresponding to an integrated luminosity of 27.8 nbsup-1/sup and 4.0 pbsup-1/sup, respectively, recorded with the ATLAS detector at the Large Hadron Collider in 2013. The p+Pb collision centrality was characterised using the total transverse energy measured in the pseudorapidity interval -4.9<η<-3.2 in the direction of the lead beam. Results are presented for the double-differential per-collision yields as a function of jet rapidity and transverse momentum (pinfT/inf) for minimum-bias and centrality-selected p+Pb collisions, and are compared to the jet rate from the geometric expectation. The total jet yield in minimum-bias events is slightly enhanced above the expectation in a pinfT/inf-dependent manner but is consistent with the expectation within uncertainties. The ratios of jet spectra from different centrality selections show a strong modification of jet production at all pinfT/inf at forward rapidities and for large pinfT/inf at mid-rapidity, which manifests as a suppression of the jet yield in central events and an enhancement in peripheral events. These effects imply that the factorisation between hard and soft processes is violated at an unexpected level in proton-nucleus collisions. Furthermore, the modifications at forward rapidities are found to be a function of the total jet energy only, implying that the violations may have a simple dependence on the hard parton-parton kinematics. © 2015 CERN for the benefit of the ATLAS Collaboration.

Centrality dependence of high-p(T) D meson suppression in Pb-Pb collisions at root s(NN)=2.76 TeV / Adam,J / JOURNAL OF HIGH ENERGY PHYSICS. - 2015

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The nuclear modification factor, R-AA, of the prompt charmed mesons D-0, D+ and D*+, and their antiparticles, was measured with the ALICE detector in Pb-Pb collisions at a centre-of-mass energy root s(NN) = 2 : 76 TeV in two transverse momentum intervals, 5 p(T) 8 GeV/c and 8 p(T) 16 GeV/c, and in six collision centrality classes. The R-AA shows a maximum suppression of a factor of 56 in the 10% most central collisions. The suppression and its centrality dependence are compatible within uncertainties with those of charged pions. A comparison with the R-AA of non-prompt J/psi from B meson decays, measured by the CMS Collaboration, hints at a larger suppression of D mesons in the most central collisions.

Centrality dependence of inclusive J/psi production in p-Pb collisions at root S-NN=5.02TeV / Adam,J/ JOURNAL OF HIGH ENERGY PHYSICS. - 2015

Annotation:

We present a measurement of inclusive J/psi production in p-Pb collisions at root S-NN = 5.02 TeV as a function of the centrality of the collision, as estimated from the energy deposited in the Zero Degree Calorimeters. The measurement is performed with the ALICE detector down to zero transverse momentum, p(T), in the backward (-4.46 y(cms) -2.96) and forward (2.03 y(cms) 3.53) rapidity intervals in the dimuon decay channel and in the mid-rapidity region (-1.37 y(cms) 0.43) in the dielectron decay channel. The backward and forward rapidity intervals correspond to the Pb-going and p-going direction, respectively. The p(T)-differential J/psi production cross section at backward and forward rapidity is measured for several centrality classes, together with the corresponding average p(T) and p(T)(2) values. The nuclear modification factor is presented as a function of centrality for the three rapidity intervals, and as a function of p(T) for several centrality classes at backward and forward rapidity. At mid-and forward rapidity, the J/psi yield is suppressed up to 40% compared to that in pp interactions scaled by the number of binary collisions. The degree of suppression increases towards central p-Pb collisions at forward rapidity, and with decreasing p(T) of the J/psi. At backward rapidity, the nuclear modification factor is compatible with unity within the total uncertainties, with an increasing trend from peripheral to central p-Pb collisions.

Centrality dependence of particle production in p-Pb collisions at root s(NN)=5.02 TeV / Adam,J / PHYSICAL REVIEW C. - 2015.

Annotation:

We report measurements of the primary charged-particle pseudorapidity density and transverse momentum distributions in p-Pb collisions at root s(NN) = 5.02 TeV and investigate their correlation with experimental observables sensitive to the centrality of the collision. Centrality classes are defined by using different event-activity estimators, i.e., charged-particle multiplicities measured in three different pseudorapidity regions as well as the energy measured at beam rapidity (zero degree). The procedures to determine the centrality, quantified by the number of participants (N-part) or the number of nucleon-nucleon binary collisions (N-coll) are described. We show that, in contrast to Pb-Pb collisions, in p-Pb collisions large multiplicity fluctuations together with the small range of participants available generate a dynamical bias in centrality classes based on particle multiplicity. We propose to use the zero-degree energy, which we expect not to introduce a dynamical bias, as an alternative event-centrality estimator. Based on zero-degree energy-centrality classes, the N-part dependence of particle production is studied. Under the assumption that the multiplicity measured in the Pb-going rapidity region scales with the number of Pb participants, an approximate independence of the multiplicity per participating nucleon measured at mid-rapidity of the number of participating nucleons is observed. Furthermore, at high-pT the p-Pb spectra are found to be consistent with the pp spectra scaled by N-coll for all centrality classes. Our results represent valuable input for the study of the event-activity dependence of hard probes in p-Pb collisions and, hence, help to establish baselines for the interpretation of the Pb-Pb data.

Chadeeva,M. Hadron shower decomposition in a highly granular calorimeter / Chadeeva,M. / Journal of Physics: Conference Series. - 2015.

Annotation:

The spatial development of showers induced by positive hadrons with momenta 10-80 GeV in the highly granular CALICE scintillator-steel analogue hadronic calorimeter is analysed. The parametrisation of both longitudinal and radial shower profiles with the two- component functions are fit to the test beam data and simulations using the physics lists QGSP-BERT and FTFP-BERT from GEANT4 version 9.6 patch 01. The shower parameters, describing the longitudinal tail and radial halo, are in good agreement between data and simulations and are similar for pions and protons. For the longitudinal development, the most significant difference between data and simulations is in the relative containment of the separated components. For the radial development, the core slope parameter is underestimated by simulations. The physics list FTFP-BERT gives a very good description of proton showers in the studied energy range and gives better predictions of the pion shower development than QGSP-BERT.

Change of phase composition of metals by the radiation of the fiber laser for management of their magnetic characteristics / Tret'Yakov,E.V. / Journal of Physics: Conference Series. - 2015.

Annotation:

Main technological parameters of heat treatment of ferromagnetic alloy samples of special stainless steel were experimentally determined in order to create the paramagnetic zone of a given size there. © Published under licence by IOP Publishing Ltd.

Characteristics of silicon carbide detectors / Rozov,S.V. / Instruments and Experimental Techniques. - 2015.

Annotation:

A procedure for manufacturing detectors (with a diameter of ∼1 mm and thickness of 0.1 mm) based on high-purity epitaxial layers of 4H-SiC polytype is described, and results of investigation of their parameters are presented. It is shown that the designed detectors have good spectrometric characteristics in α particle detection in a wide energy range. The measured 241Am γ ray spectra are also given.

Charge distribution of superheavy elements in galactic cosmic rays on base of investigations in olivine crystals from meteorites / Bagulya,A.V. / AIP Conference Proceedings. - 2015.

Annotation:

An original method of studying chemically etched tracks of heavy nuclei in olivine from pallasite meteorites was used to obtain a charge distribution of approximately 9000 nuclei with charges above 55 in galactic cosmic rays. Three superheavy nuclei with the charges in the range of 105<Z<130 were detected. Regression analysis enabled to amend the charge of one of these nuclei up to the value 119-6 +10 with the probability of 95%. Such nuclei have to form islands of stability of superheavy elements; their occurrence in nature supports the validity of theoretical predictions and justifies efforts for their synthesis under the Earth conditions. © 2015 AIP Publishing LLC.

Charged jet cross sections and properties in proton-proton collisions at root s=7 TeV / Abelev,B / PHYSICAL REVIEW D. - 2015.

Annotation:

The differential charged jet cross sections, jet fragmentation distributions, and jet shapes are measured in minimum bias proton-proton collisions at center-of-mass energy root s = 7 TeV using the ALICE detector at the LHC. Jets are reconstructed from charged particle momenta in the midrapidity region using the sequential recombination k(T) and anti-k(T) as well as the SISCone jet finding algorithms with several resolution parameters in the range R = 0.2-0.6. Differential jet production cross sections measured with the three jet finders are in agreement in the transverse momentum (p(T)) interval 20 p(T)(jet,ch) 100 GeV/c. They are also consistent with prior measurements carried out at the LHC by the ATLAS Collaboration. The jet charged particle multiplicity rises monotonically with increasing jet p(T), in qualitative agreement with prior observations at lower energies. The transverse profiles of leading jets are investigated using radial momentum density distributions as well as distributions of the average radius containing 80% ( R-80 ) of the reconstructed jet p(T). The fragmentation of leading jets with R = 0.4 using scaled p(T) spectra of the jet constituents is studied. The measurements are compared to model calculations from event generators (PYTHIA, PHOJET, HERWIG). The measured radial density distributions and R-80 distributions are well described by the PYTHIA model (tune Perugia-2011). The fragmentation distributions are better described by HERWIG.

Charged-to-neutral correlation at forward rapidity in Au plus Au collisions at root s(NN)=200 GeV / Adamczyk,L / PHYSICAL REVIEW C. - 2015.

Annotation:

Event-by-event fluctuations of the multiplicities of inclusive charged particles and photons at forward rapidity in Au + Au collisions at root s(NN) = 200 GeV have been studied. The dominant contribution to such fluctuations is expected to come from correlated production of charged and neutral pions. We search for evidence of dynamical fluctuations of different physical origins. Observables constructed out of moments of multiplicities are used as measures of fluctuations. Mixed events and model calculations are used as base lines. Results are compared to the dynamical net-charge fluctuations measured in the same acceptance. A nonzero statistically significant signal of dynamical fluctuations is observed in excess to the model prediction when charged particles and photons are measured in the same acceptance. We find that, unlike dynamical net-charge fluctuation, charge-neutral fluctuation is not dominated by correlation owing to particle decay. Results are compared to the expectations based on the generic production mechanism of pions owing to isospin symmetry, for which no significant (1%) deviation is observed.

Cherenkov Water Detector NEVOD: A New Stage of Development / Kindin,V.V. / Physics Procedia. - 2015.

Annotation:

The new detecting system of the Cherenkov water detector of the Unique Scientific Facility "Experimental complex NEVOD" located at the ground level is described. During the development of the detecting system, two tasks have been solved: providing a hodoscopic mode for registration of single muon tracks in 4π-geometry and a calorimetric mode for measurements of the energy deposit of cascades and high-multiplicity muon bundles. © 2015 The Authors.

Chernyakov,Y.B. New method for constructing semi-invariants and integrals of the full symmetric (Formula Presented.) Toda lattice [Theoretical and Mathematical Physics, (2015) / Chernyakov,Y.B., Sorin,A.S. / Theoretical and Mathematical Physics(Russian Federation). - 2015.

Annotation:

We consider the full symmetric representation of the Lax operator matrix of the Toda lattice, which is known as the full symmetric Toda lattice. The phase space of this system is the generic orbit of the coadjoint action of the Borel subgroup Binfn/inf sup+/supof SLinfn/inf(ℝ). This system is integrable. We propose a new method for constructing semi-invariants and integrals of the full symmetric Toda lattice. Using only the equations of motion for the Lax eigenvector matrix, we prove the existence of the semi-invariants that are Plücker coordinates in the corresponding projective spaces. We use these semi-invariants to construct the integrals. Our new approach provides simple exact formulas for the full set of independent semi-invariants and integrals expressed in terms of the Lax matrix and also in terms of its eigenvector and eigenvalue matrices of the full symmetric Toda lattice without using the chopping and Kostant procedures. We describe the structure of the additional integrals of motion as functions on the flag space modulo the Toda flows and show how the Plücker coordinates of different projective spaces define different families of the additional integrals. © 2015, Pleiades Publishing, Ltd.

Coherent ρsup0/sup photoproduction in ultra-peripheral Pb-Pb collisions at √sups/supNN=2.76 TeV / TheALICEcollaboration / Journal of High Energy Physics. - 2015.

Annotation:

We report the first measurement at the LHC of coherent photoproduction of ρsup0/sup mesons in ultra-peripheral Pb-Pb collisions. The invariant mass and transverse momentum distributions for ρsup0/sup production are studied in the πsup+/supπsup−/sup decay channel at mid-rapidity. The production cross section in the rapidity range |y| < 0.5 is found to be dσ/dy = 425 ± 10(stat.)inf− 50/inf sup+ 42/sup (sys.) mb. Coherent ρsup0/sup production is studied with and without requirement of nuclear breakup, and the fractional yields for various breakup scenarios are presented. The results are compared with those from lower energies and with model predictions. © 2015, The Author(s).

Coherent ψ(2S) photo-production in ultra-peripheral PbPb collisions at sNN=2.76 TeV / Adam,J. / Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 2015.

Annotation:

We have performed the first measurement of the coherent ψ(2S) photo-production cross section in ultra-peripheral Pb. Pb collisions at the LHC. This charmonium excited state is reconstructed via the ψ(2S)→l+l- and ψ(2S)→J/ψπ+π- decays, where the J/ψ decays into two leptons. The analysis is based on an event sample corresponding to an integrated luminosity of about 22 μb-1. The cross section for coherent ψ(2S) production in the rapidity interval -0.9<y<0.9 is dσψ(2S)coh/dy=0.83±0.19(stat+syst) mb. The ψ(2S) to J/ψ coherent cross section ratio is 0.34-0.07+0.08(stat+syst). The obtained results are compared to predictions from theoretical models. © 2015 CERN for the benefit of the ALICE Collaboration.

Colored HOMFLY polynomials of knots presented as double fat diagrams / Ramadevi,P. / Journal of High Energy Physics. - 2015

Annotation:

Many knots and links in Ssup3/sup can be drawn as gluing of three manifolds with one or more four-punctured Ssup2/sup boundaries. We call these knot diagrams as double fat graphs whose invariants involve only the knowledge of the fusion and the braiding matrices of four -strand braids. Incorporating the properties of four-point conformal blocks in WZNW models, we conjecture colored HOMFLY polynomials for these double fat graphs where the color can be rectangular or non-rectangular representation. With the recent work of Gu-Jockers, the fusion matrices for the non-rectangular [21] representation, the first which involves multiplicity is known. We verify our conjecture by comparing with the [21] colored HOMFLY of many knots, obtained as closure of three braids. The conjectured form is computationally very effective leading to writing [21]-colored HOMFLY polynomials for many pretzel type knots and non-pretzel type knots. In particular, we find class of pretzel mutants which are distinguished and another class of mutants which cannot be distinguished by [21] representation. The difference between the [21]-colored HOMFLY of two mutants seems to have a general form, with A-dependence completely defined by the old conjecture due to Morton and Cromwell. In particular, we check it for an entire multi-parametric family of mutant knots evaluated using evolution method. © 2015, The Author(s).

Colored knot polynomials for arbitrary pretzel knots and links / Galakhov,D. / Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 2015.

Annotation:

A very simple expression is conjectured for arbitrary colored Jones and HOMFLY polynomials of a rich (g+1)-parametric family of pretzel knots and links. The answer for the Jones and HOMFLY is fully and explicitly expressed through the Racah matrix of Uq(SUN), and looks related to a modular transformation of toric conformal block.

Colored knot polynomials: HOMFLY in representation [2, 1] / Mironov,A. / International Journal of Modern Physics A. - 2015.

Annotation:

This paper starts a systematic description of colored knot polynomials, beginning from the first non-(anti)symmetric representation R = [2, 1]. The project involves several steps: (i) parametrization of big families of knots á la [A. Mironov and A. Morozov, arXiv:1506.00339], (ii) evaluating Racah/mixing matrices for various numbers of strands in various representations á la [A. Mironov, A. Morozov and An. Morozov, J. High Energy Phys. 03, 034 (2012), arXiv:1112.2654], (iii) tabulating and collecting the results at http://www.knotebook.org. In this paper, we discuss only the representation R = [2, 1] and construct all necessary ingredients that allow one to evaluate knot/links represented by three-strand closed parallel braids with inserted double-fat fingers. In particular, it is used to evaluate knots from a 7-parametric family. This family contains over 80% of knots with up to 10 intersections, but does not include mutants. © 2015 World Scientific Publishing Company.

Combined Measurement of the Higgs Boson Mass in pp Collisions at root s=7 and 8 TeV with the ATLAS and CMS Experiments / Aad,G / PHYSICAL REVIEW LETTERS. - 2015.

Annotation:

A measurement of the Higgs boson mass is presented based on the combined data samples of the ATLAS and CMS experiments at the CERN LHC in the H -- gamma gamma and H -- ZZ -- 4l decay channels. The results are obtained from a simultaneous fit to the reconstructed invariant mass peaks in the two channels and for the two experiments. The measured masses from the individual channels and the two experiments are found to be consistent among themselves. The combined measured mass of the Higgs boson is m(H) = 125.09 +/- 0.21 (stat) +/- 0.11 (syst) GeV.

Comparative analyses of low melting metals application with capillary-pore systems in tokamak conditions / Vertkov,A.V., Semenov,V.V., Lyublinski,I.E. / Problems of Atomic Science and Technology, Series Thermonuclear Fusion. - 2015.

Annotation:

Capillary-pore systems (CPS) with liquid metals are considered as advanced plasma facing elements (PFE) for application in DEMO-type fusion reactor and fusion neutron source. The main advantages of low melting metals in CPS with respect to solid materials are the possibility to provide surface self-healing and high resistance to degradation of properties. The estimation of opportunity of liquid Li, Ga and Sn application is carried out on the basis of their physical, chemical and technological properties, and with respect to prospective design of the tokamak in-vessel elements. The temperature limit for normal operation of CPS with Li, Ga, Sn is about 550-600 C. For Li application it is determined by appropriate flux to the plasma due to evaporation and for Ga and Sn - by corrosion resistance limit. Surface temperature analysis for possible in-vessel element design has shown the similar power flux limit ∼18-20 MW/m2 for Li, Ga and Sn application at normal operation. It is clear that application of liquid metals with low vapor pressure (Ga, Sn) does not increase PFE operation limit. The property combination, well-demonstrated possibility for surface self-healing, favorable effect on tokamak plas-ma parameters offer the advantage of Li. The CPS with Li has the priority for ELEs and at disruption conditions taking into account very high latent heat of vaporization and screening effect with re-radiation. Now Li is the most attractive and most investigated liquid metal for fusion devices application with CPS.

Comparative nonempirical analysis of emission properties of the Ar-MeIinfn/inf glow discharge (Me = Ga, Zn, Sn, In, Bi, Tl) / Deminsky,M. / Journal of Physics D: Applied Physics. - 2015.

Annotation:

A screening procedure is applied for several candidates (GaIinf3/inf, ZnIinf2/inf, SnIinf2/inf, InI, BiIinf3/inf, TlI) in respect of their light emission properties in a Ar-MeIinfn/inf glow discharge. Candidates are compared in terms of emission efficiency for a wide range of external conditions: temperature, matrix gas pressure, and MeIinfn/inf vapor pressure. The differences among the systems are explained by analyzing the kinetic mechanisms of formation, excitation, and loss of the emitting atoms. Analysis of the trends in the electronic structures of emitters (atoms) and precursors (molecules), as well as the stoichiometry and endothermicity of the plasma-chemical reactions, was made, and matched with selection rules. © 2015 IOP Publishing Ltd.

Comparative study of spark plasma sintering and high voltage electric discharge consolidation of zirconium nitride powder / Lee,G. / Advances in Powder Metallurgy and Particulate Materials - Proceedings of the 2015 International Conference on Powder Metallurgy and Particulate Materials, PowderMet 2015.

Annotation:

The densification behavior of zirconium nitride (ZrN) powder is scrutinized for various experimental conditions such as temperature, pressure and electric current imposed by spark plasma sintering (SPS) and high voltage electric discharge consolidation (HVEDC) techniques. The microstructure and porosity are examined by scanning electron microscopy, Archimedes density measurements, and pycnometry. The densification maps for ZrN powder using both processing technique were developed based on the obtained experimental data. The results of the two considered consolidation techniques are comparatively assessed.

Comparative validation of Monte Carlo codes for the conversion of a research reactor / Hanan,N.A. / Annals of Nuclear Energy. - 2015.

Annotation:

This paper presents the calculation results of the set of test problems for a research reactor with a tube-type low enriched uranium (LEU, 19.7 w/o, U-9%Mo) fuel and oxide high enriched uranium (HEU, 90 w/o) fuel, a light water moderator, and a beryllium reflector. The static cases and the depletion problem were examined. Calculations were performed using continuous energy Monte Carlo codes: MCNP (+MCREB for burnup calculation), MCU-PTR, and SERPENT 2. The impact of the cross-section libraries used for a particular problem on the calculated results was investigated.

Comparison of the Z/gamma* plus jets to gamma plus jets cross sections in pp collisions at root s=8 TeV / Khachatryan,V / JOURNAL OF HIGH ENERGY PHYSICS. - 2015

Annotation:

A comparison of the differential cross sections for the processes Z/gamma* + jets and photon (gamma)+ jets is presented. The measurements are based on data collected with the CMS detector at root s = 8TeV corresponding to an integrated luminosity of 19.7 fb(-1). The differential cross sections and their ratios are presented as functions of p(T). The measurements are also shown as functions of the jet multiplicity. Differential cross sections are obtained as functions of the ratio of the Z/gamma* p(T) to the sum of all jet transverse momenta and of the ratio of the Z/gamma* p(T) to the leading jet transverse momentum. The data are corrected for detector effects and are compared to simulations based on several QCD calculations.

CONCEPTUAL DEVELOPMENT OF A 600-1000 MeV PROTON BEAM ACCELERATOR-DRIVER WITH AVERAGE BEAM POWER 1 MW / Batyaev,VF / ATOMIC ENERGY. - 2015.

Annotation:

The results of a comprehensive analysis of the possibility of developing in our country a powerful proton accelerator-driver as an element of subcritical electro-nuclear facility are presented. The investigations are performed taking account of the latest advances of accelerator technology and the real capabilities of industry. The design layout developed for the accelerator is discussed. It is shown that in principle a prototype of a similar to 1 GeV accelerator-driver with current 1-5 mA, which can subsequently be increased to 10-15 mA, can be built in Russia.

Constraints on new phenomena via Higgs boson couplings and invisible decays with the ATLAS detector / Aad,G / JOURNAL OF HIGH ENERGY PHYSICS. - 2015

Annotation:

The ATLAS experiment at the LHC has measured the Higgs boson couplings and mass, and searched for invisible Higgs boson decays, using multiple production and decay channels with up to 4.7 fb(-1) of pp collision data at root S = 7 TeV and 20.3 fb(-1) at root s = 8 TeV. In the current study, the measured production and decay rates of the observed Higgs boson in the gamma gamma, ZZ, WW, Z gamma, bb, tau tau, and mu mu decay channels, along with results from the associated production of a Higgs boson with a top-quark pair, are used to probe the scaling of the couplings with mass. Limits are set on parameters in extensions of the Standard Model including a composite Higgs boson, an additional electroweak singlet, and two-Higgs-doublet models. Together with the measured mass of the scalar Higgs boson in the gamma gamma and ZZ decay modes, a lower limit is set on the pseudoscalar Higgs boson mass of m(A) 370 GeV in the "hMSSM" simplified Minimal Supersymmetric Standard Model. Results from direct searches for heavy Higgs bosons are also interpreted in the hMSSM. Direct searches for invisible Higgs boson decays in the vector-boson fusion and associated production of a Higgs boson with W/Z (Z - ll, W/Z - jj) modes are statistically combined to set an upper limit on the Higgs boson invisible branching ratio of 0.25. The use of the measured visible decay rates in a more general coupling fit improves the upper limit to 0.23, constraining a Higgs portal model of dark matter.

Constraints on the off-shell Higgs boson signal strength in the high-mass ZZ and WW final states with the ATLAS detector / ATLASCollaboration / European Physical Journal C. - 2015.

Annotation:

Measurements of the ZZ and WW final states in the mass range above the 2minfZ/infand 2minfW/infthresholds provide a unique opportunity to measure the off-shell coupling strength of the Higgs boson. This paper presents constraints on the off-shell Higgs boson event yields normalised to the Standard Model prediction (signal strength) in the ZZ 4l ZZ → 2ℓ2ν and WW → eνμν final states. The result is based on pp collision data collected by the ATLAS experiment at the LHC, corresponding to an integrated luminosity of 20.3 fbsup-1/supat a collision energy of s=8 TeV. Using the $$CL_s$$CLs method, the observed 95% confidence level (CL) upper limit on the off-shell signal strength is in the range 5.1–8.6, with an expected range of 6.7–11.0. In each case the range is determined by varying the unknown gg → ZZ and gg → WW background K-factor from higher-order quantum chromodynamics corrections between half and twice the value of the known signal K-factor. Assuming the relevant Higgs boson couplings are independent of the energy scale of the Higgs boson production, a combination with the on-shell measurements yields an observed (expected) 95% CL upper limit on (formula presented) in the range 4.5–7.5 (6.5–11.2) using the same variations of the background K-factor. Assuming that the unknown gg → VV background K-factor is equal to the signal K-factor, this translates into an observed (expected) 95 $$$$% CL upper limit on the Higgs boson total width of 22.7 (33.0) MeV. © 2015, CERN for the benefit of the ATLAS collaboration.

Constraints on the pMSSM, AMSB model and on other models from the search for long-lived charged particles in proton-proton collisions at root s=8TeV / Khachatryan,V / EUROPEAN PHYSICAL JOURNAL C. - 2015.

Annotation:

Stringent limits are set on the long-lived lepton-like sector of the phenomenological minimal supersymmetric standard model (pMSSM) and the anomaly-mediated super-symmetry breaking (AMSB) model. The limits are derived from the results presented in a recent search for long-lived charged particles in proton-proton collisions, based on data collected by the CMS detector at a centre-of-mass energy of 8 TeV at the Large Hadron Collider. In the pMSSM parameter sub-space considered, 95.9% of the points predicting charginos with a lifetime of at least 10 ns are excluded. These constraints on the pMSSM are the first obtained at the LHC. Charginos with a lifetime greater than 100 ns and masses up to about 800 GeV in the AMSB model are also excluded. The method described can also be used to set constraints on other models.

Contribution of Electric Current into Densification Kinetics During Spark Plasma Sintering of Conductive Powder / Olevsky,EugeneA / JOURNAL OF THE AMERICAN CERAMIC SOCIETY. - 2015.

Annotation:

The shrinkage kinetics of a conductive material (copper powder) under spark plasma sinter-forging conditions in the presence and absence of the electric current passing directly through the specimen is investigated from both experimental and theoretical points of view. The experiments on the current-assisted and current-insulated spark plasma sinter-forging are conducted using specially developed spark plasma sintering tooling which has a number of particular features. The tooling enables direct temperature measurement at the free lateral surface of a powder sample as well as the simultaneous insitu measurement of the radius and height of a porous cylindrical sample during spark plasma sinter-forging, rendering conditions of bi-axial dilatometry. The continuum theory of sintering-based constitutive model of free upsetting (hot forging with free lateral surface) is refined taking into account the obtained experimental data on the current-insulated mode of spark plasma sinter-forging. It is shown that the model framework traditionally utilized for the description of hot deformation of powder materials is not suitable for the simulation of the considered current-assisted spark plasma sintering modes. Thus, the necessity of the development of new, specific to spark plasma sintering, constitutive models taking into account the direct contributions of electric current into mass transfer, is demonstrated.

Correcting data from the URAGAN muon hodoscope for the temperature profile of the atmosphere, using data from the CAO, GDAS, and ALISA-SK receiving station for 2007–2014 / Dmitrieva,A.N. / Bulletin of the Russian Academy of Sciences: Physics. - 2015.

Annotation:

In order to analyze muon flux variations caused by extra-atmospheric processes, it is necessary to introduce corrections for meteorological effects. To take the temperature effect into account, we must know the temperature profile of the atmosphere. Vertical temperature profiles obtained from NOAA satellites and calculated using the model of the Global Data Assimilation System (GDAS) are compared to data from the Central Aerological Observatory (CAO, Dolgoprudny) for standard isobaric levels. The average temperature difference for most levels does not exceed 1 K. A comparison of the data from the URAGAN hodoscope, corrected for the temperature effect using data from the CAO, NOAA, and GDAS, shows excellent mutual agreement. A series of integral time counting rate and the anisotropy of the muon flux for 2007–2014, corrected for atmospheric effects, are presented. © 2015, Allerton Press, Inc.

Corrosion resistance of V-4Ti-4Cr alloy in convection flow of eutectic Na-K alloy / Semenov,V.V. / Inorganic Materials: Applied Research. - 2015.

Annotation:

The corrosion resistance of V-Ti-Cr alloys in contact with a eutectic Na-K melt have been evaluated from experiments on the compatibility of V-4Ti-4Cr alloy specimens with a convection flow of the Na-K eutectic. In the test system made of the same vanadium-based alloy, the maximum temperature was 650°C, the temperature drop was 150°C, and the duration of the tests was 500 h. The experiments have shown that, under the conditions of the tests carried out in the Na-K eutectic with an initial concentration of oxygen of 0.04 wt %, the V-4Ti-4Cr alloy undergoes intense mass transfer. The solid metal absorbs the oxygen impurity from the liquid melt. The observed effects agree with the previously drawn conclusions on the effect of the oxygen impurity on the solubility of vanadium in the Na-K eutectic. Provided that the intensity of the source of the oxygen impurity in the corrosion system is limited, one might expect acceptable corrosion compatibility of the V-4Ti-4Cr alloy with the Na-K eutectic. © 2015, Pleiades Publishing, Ltd.

Cudell,J.R. Dark atoms with nuclear shell: A status review / Cudell,J.R., Khlopov,M. / International Journal of Modern Physics D. - 2015.

Annotation:

Among dark atom scenarios, the simplest and most predictive one is that of O-helium (OHe) dark atoms, in which a leptonlike doubly charged particle (Formula presented.) is bound to a primordial helium nucleus, and is the main constituent of dark matter. The OHe cosmology has several successes: it leads to a warmer-than-cold-dark matter scenario for large-scale-structure formation, it can provide an explanation for the excess in positron annihilation line in the galactic bulge and it may explain the results of direct dark matter searches. This model liberates the physics of dark atoms from many unknown features of new physics, but it is still not free from astrophysical uncertainties. It also demands a deeper understanding of the details of known nuclear and atomic physics, which are still somewhat unclear in the case of nuclear interacting “atomic” shells. These potential problems of the OHe scenario are also discussed. © 2015 World Scientific Publishing Company

Current status of the MONICA experiment to study the ionic composition of solar cosmic rays / Zamiatin,N.I. / Bulletin of the Russian Academy of Sciences: Physics. - 2015.

Annotation:

The current status of the MONICA experiment to study fluxes of cosmic ray ions from H to Ni in the energy range of 10–300 MeV in the vicinity of the Earth is described. The main scientific objective of the MONICA experiment is to measure the ionic and isotope compositions and energy spectra of solar cosmic rays for individual solar events, and to study the time evolution of these characteristics. The MONICA experiment will also allow us to investigate the ionic and isotope compositions of the anomalous cosmic ray component, galactic cosmic rays, and fluxes of nuclei in the Earth’s radiation belt. Ion fluxes will be observed using the MONICA large-aperture multilayer semiconductor spectrometer telescope on board a spacecraft in a circumterrestrial polar orbit with an altitude on the order of 600 km. This will enable us to measure the charges of ions with energies over 10 MeV/nucleon by using the Earth’s magnetic field as a charge separator. The geometric factor of the instrument is 100 cmsup2/sup sr; its angular resolution is 1°. © 2015, Allerton Press, Inc.

Dark Coulomb binding of heavy neutrinos of fourth family / Belotsky,K.M. / International Journal of Modern Physics D. - 2015.

Annotation:

Direct dark matter searches put severe constraints on the weakly interacting massive particles (WIMPs). These constraints cause serious troubles for the model of stable neutrino of fourth generation with mass around 50(Formula presented.)GeV. Though the calculations of primordial abundance of these particles make them in the charge symmetric case a sparse subdominant component of the modern dark matter, their presence in the universe would exceed the current upper limits by several orders of the magnitude. However, if quarks and leptons of fourth generation possess their own Coulomb-like (Formula presented.)-interaction, recombination of pairs of heavy neutrinos and antineutrinos and their annihilation in the “neutrinium” atoms can play important role in their cosmological evolution, reducing their modern abundance far below the experimental upper limits. The model of stable fourth generation assumes that the dominant part of dark matter is explained by excessive (Formula presented.) antiquarks, forming (Formula presented.) charged clusters, bound with primordial helium in nuclear-interacting O-helium (OHe) dark atoms. The (Formula presented.) charge conservation implies generation of the same excess of fourth generation neutrinos, potentially dangerous WIMP component of this scenario. We show that due to (Formula presented.)-interaction recombination of fourth neutrinos with OHe hides these WIMPs from direct WIMP searches, leaving the negligible fraction of free neutrinos, what makes their existence compatible with the experimental constraints. © 2015 World Scientific Publishing Company

Decrease of atmospheric neutron counts observed during thunderstorms / Alekseenko,V. / Physical Review Letters. - 2015.

Annotation:

We report here, in brief, some results of the observation and analysis of sporadic variations of atmospheric thermal neutron flux during thunderstorms. The results obtained with unshielded scintillation neutron detectors show a prominent flux decrease correlated with meteorological precipitations after a long dry period. No observations of neutron production during thunderstorms were reported during the three-year period of data recording. © 2015 American Physical Society.

Denisenko,A.S. Application of principal components analysis results in visual network analysis / Denisenko,A.S., Krylov,G.O. / Biosciences Biotechnology Research Asia. - 2015.

Annotation:

The paper deals with the application of principal components analysis in a roleof a preprocessor of the source data and its role in visual network analysis process. Such kind of PCA application provides highlighting the most valuable objects in the source selection. By the example of analyzing financial data of companies of certain industry in order to measure their activity level authors show that principal components analysis could be used as a preprocessor for further analysis. As a result of the research, they show the integration and visualization of the integral scores in the process of visual network analysis and their role in simplifying the large data processing.

Densification of zirconium nitride by spark plasma sintering and high voltage electric discharge consolidation: A comparative analysis / Lee,G. / Ceramics International. - 2015.

Annotation:

The densification behavior of zirconium nitride powder is investigated for various temperature and pressure conditions imposed by spark plasma sintering and high voltage electric discharge consolidation techniques. The crystal structure, chemical composition, porosity, and grain size of the powders and processed specimens are analyzed by X-ray diffraction, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. The outcomes of the two considered consolidation techniques are comparatively assessed. Vickers micro-hardness of the processed ZrN specimens is investigated, and hardness dependence on porosity is analyzed. The densification mechanism of ZrN consolidated by spark plasma sintering is revealed by applying the constitutive equation of the continuum theory of sintering, and it turns out to be a similar mechanism to hot pressing. Application of the sintering constitutive equations shows that the mechanism of ZrN densification by high voltage electric discharge consolidation method depends on the magnitude of the applied voltage. © 2015 Elsevier Ltd and Techna Group S.r.l.

Design and Performance of the ARIANNA HRA-3 Neutrino Detector Systems / Barwick,SW / IEEE TRANSACTIONS ON NUCLEAR SCIENCE. - 2015.

Annotation:

We report on the development, installation, and operation of the first three of seven stations deployed at the ARIANNA site's pilot Hexagonal Radio Array (HRA) in Antarctica. The primary goal of the ARIANNA project is to observe ultrahigh energy ( 100 PeV) cosmogenic neutrino signatures using a large array of autonomous stations, each 1 km apart on the surface of the Ross Ice Shelf. Sensing radio emissions of 100 MHz to 1 GHz, each station in the array contains RF antennas, amplifiers, 1.92 G-sample/s, 850 MHz bandwidth signal acquisition circuitry, pattern-matching trigger capabilities, an embedded CPU, 32 GB of solid-state data storage, and long-distance wireless and satellite communications. Power is provided by the sun and buffered in LiFePO4 storage batteries, and each station consumes an average of 7 W of power. Operation on solar power has resulted in = 58% per calendar-year live-time. The station's pattern-trigger capabilities reduce the trigger rates to a few milli-Hertz with 4-sigma voltage thresholds while retaining good stability and high efficiency for neutrino signals. The timing resolution of the station has been found to be 0.049 ns, RMS, and the angular precision of event reconstructions of signals bounced off of the sea-ice interface of the Ross Ice Shelf ranged from 0.14 to 0.17 degrees.

Design, construction and operation of a low-power, autonomous radio-frequency data-acquisition station for the TARA experiment / Kunwar,S / NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT. - 2015.

Annotation:

Employing a 40-kW, 54.1 MHz radio-frequency transmitter just west of Delta, UT, the TARA (Telescope Array RAdar) experiment seeks radar detection of extensive air showers (EAS) initiated by ultra-high energy cosmic rays (UHECR). For UHECR with energies in excess of 10(19) eV, the Doppler-shifted "chirps" resulting from [AS shower core radar reflections should be observable above background (dominantly galactic) at distances of tens of km from the TARA transmitter. In order to stereoscopically reconstruct cosmic ray chirps, two remote, autonomous self-powered receiver stations have been deployed. Each remote station (RS) combines both low power consumption and low cost. Triggering logic, the powering and communication systems, ancl some specific details of hardware components are discussed. (C) 2015 Elsevier B.V. All rights reserved.

Detection of a change in the North-South ratio of count rates of particles of high-energy cosmic rays during a change in the polarity of the magnetic field of the Sun / Adriani,O / JETP LETTERS. - 2015.

Annotation:

A change in the ratio of the intensities of particles of high-energy cosmic rays arriving from the North and South in the time interval of 2010-2014 has been detected with a calorimeter entering into the experimental complex of the PAMELA satellite experiment since June 2006. The polarity of the magnetic field of the Sun changed in a part of this time interval. Thus, the results indicate that the North-South asymmetry of cosmic ray fluxes is related to the magnetic field of the Sun.

Determination of radioactive waste activity in containers using a xenon gamma spectrometer / P’ya,S.N. / Bulletin of the Lebedev Physics Institute. - 2015.

Annotation:

A xenon gamma spectrometer (XGS) with a sensitive volume of 6 liters is described. Physico-technical characteristics of the gamma spectrometer, determined using radioactive sources of the set of standard spectrometric gamma sources, are presented. Gamma spectra of radioactive waste in a 3.4-msup3/sup container for solid radioactive waste are measured, and isotope activities are determined. The XGS is simulated by the Monte Carlo method using the GEANT4 package. The activities are determined by a combined method with an analysis of experimental spectra and simulated data. It is shown that the XGS has good metrological capabilities for characterizing radioactive waste, including nuclide identification and their activity estimation. © 2015, Allerton Press, Inc.

Determination of spin and parity of the Higgs boson in the WW* - ev mu v decay channel with the ATLAS detector / Aad,G / EUROPEAN PHYSICAL JOURNAL C. - 2015.

Annotation:

Studies of the spin and parity quantum numbers of the Higgs boson in the WW* - ev mu v final state are presented, based on proton-proton collision data collected by the ATLAS detector at the Large Hadron Collider, corresponding to an integrated luminosity of 20.3 fb(-1) at a centre-of-mass energy of root s = 8 TeV. The Standard Model spin-parity J(CP) = 0(++) hypothesis is compared with alternative hypotheses for both spin andCP. The case where the observed resonance is a mixture of the Standard-Model-like Higgs boson and CP-even (J(CP) = 0(++)) or CP-odd (J(CP) = 0(+-)) Higgs boson in scenarios beyond the Standard Model is also studied. The data are found to be consistent with the Standard Model prediction and limits are placed on alternative spin and CP hypotheses, including CP mixing in different scenarios.

Determination of the Ratio of b -Quark Fragmentation Fractions fs /fd in pp Collisions at s=7 TeV with the ATLAS Detector / Aad,G. / Physical Review Letters. - 2015.

Annotation:

With an integrated luminosity of 2.47 fb-1 recorded by the ATLAS experiment at the LHC, the exclusive decays Bs0→J/ψφ and Bd0→J/ψK∗0 of B mesons produced in pp collisions at s=7 TeV are used to determine the ratio of fragmentation fractions fs/fd. From the observed Bs0→J/ψφ and Bd0→J/ψK∗0 yields, the quantity (fs/fd)[B(Bs0→J/ψφ)/B(Bd0→J/ψK∗0)] is measured to be 0.199±0.004(stat)±0.008(syst). Using a recent theory prediction for [B(Bs0→J/ψφ)/B(Bd0→J/ψK∗0)] yields (fs/fd)=0.240±0.004(stat)±0.010(syst)±0.017(th). This result is based on a new approach that provides a significant improvement of the world average. © 2015 CERN., for the Atlas Collaboration. Published by the American Physical Society under the terms of the »http://creativecommons.org/licenses/by/3.0/» Creative Commons Attribution 3.0 License. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.

Determination of the top-quark pole mass using (Formula presented.) + 1-jet events collected with the ATLAS experiment in 7 TeV pp collisions / TheATLAScollaboration / Journal of High Energy Physics. - 2015.

Annotation:

Abstract: The normalized differential cross section for top-quark pair production in association with at least one jet is studied as a function of the inverse of the invariant mass of the tt¯(Formula presented.) + 1-jet system. This distribution can be used for a precise determination of the top-quark mass since gluon radiation depends on the mass of the quarks. The experimental analysis is based on proton-proton collision data collected by the ATLAS detector at the LHC with a centre-of-mass energy of 7 TeV corresponding to an integrated luminosity of 4.6 fbsup−1/sup. The selected events were identified using the lepton+jets top-quark-pair decay channel, where lepton refers to either an electron or a muon. The observed distribution is compared to a theoretical prediction at next-to-leading-order accuracy in quantum chromodynamics using the pole-mass scheme. With this method, the measured value of the top-quark pole mass, mt suppole/sup, is:mtpole=173.7±1.5stat.±1.4syst.−0.5+1.0theoryGeV.(Formula presented.). This result represents the most precise measurement of the top-quark pole mass to date.[Figure not available: see fulltext.] © 2015, The Author(s).

Determination of traces of uranium and thorium in titanium and copper used for the construction of the Russian Emission Detector 100 by inductively coupled plasma mass spectrometry / Sereda,Andrei / EUROPEAN JOURNAL OF MASS SPECTROMETRY. - 2015.

Annotation:

The Russian Emission Detector 100 (RED-100) under construction at the National Research Nuclear University MEPhI (Moscow Engineering Physics Institute) is designed to detect the presently undiscovered effect of coherent neutrino scattering. One of the factors limiting the sensitivity of the detector is the spontaneous decay of uranium and thorium in the detector materials. Radioactive impurities in detector materials at levels of parts per billion can significantly affect the sensitivity. Five random samples of titanium and one of copper-from materials used in the construction of the detector were selected for assay. The concentrations of Th-232 and U-238 were measured by inductively coupled plasma mass spectrometry (ICP-MS) in solid titanium using both solutions in acids and direct sampling by laser ablation (LA-ICP-MS). The LA-ICP-MS method allowed us to determine U-238 and Th-232 at subnanogram per gram levels. This method is much faster than ICP-MS with liquid injection. The titanium samples studied have impurities in the range between 1 ng g(-1) and 21 ng g(-1) for U-238 and 3 ng g(-1) and 31 ng g(-1) for Th-232. In copper we set upper limits of 0.4 ng g(-1) for U-238 and 1 ng g(-1) for Th-232. The total activity of the cryostat constructed from the materials studied was estimated to be 43 Bq.

Development and investigation of properties of structural materials, based on aluminum-beryllium alloys for disperse nuclear fuel / Nikitin,S.N. / Tsvetnye Metally. - 2015.

Annotation:

Research reactors are operated at rather high power densities of core energy release of and high burnup, which is connected with necessity of neutron flux density increasing and operating cost reduction. High-density dispersion uranium alloy compositions in aluminum matrix are more applicable for exploitation as fuel rod for the possibility of transition to low-enriched fuel in existing core geometries without significant reduction of neutron flux density. The main constraint to application of this composition is interaction between U - Mo granules and aluminum matrix at high burnout levels. Interaction leads to further swelling of fuel rods, reduction of matrix thermal conductivity, increase of fuel rod center temperature, formation of intermetallic compounds, through porosity and fuel rod failure. Interaction with aluminum leads to restrictions on operating conditions of U - Mo fuel in reactor, which requires the search for new alternatives. Compositions with metallic particles of uranium-molybdenum alloys in aluminum matrix, containing from 2 to 8% (wt.) of Be, are considered in this work as promising fuel compositions of dispersion-type fuel rods. The main objective of the work is experimental determination of effect of aluminum matrix beryllium doping on its kinetics of diffusion interaction with metallic uranium-molybdenum alloys. There was defined a linear decrease in the rate of interaction with increasing of beryllium content to 8% (wt.) in aluminum alloy. Comparison with other aluminum matrix alloys showed the advantage of both thermal, mechanical properties, and compatibility with uranium-molybdenum alloys.

Development of a novel method to enhance the therapeutic effect on tumours by simultaneous action of radiation and heating / Mazokhin,V.N. / International Journal of Hyperthermia. - 2015.

Annotation:

Purpose: This paper describes the development of a new type of electromagnetic hyperthermia applicator delivering dose control within large application fields and increased effectiveness by providing simultaneous action of radiation and heating (SRH) in malignant tumours, and development of a dosimetric feedback method to support SRH. Materials and methods: Single and phased arrays of flexible applicators have been developed to allow simultaneous hyperthermia and external beam therapy. A frequency of 434 MHz is used to heat near-surface and moderately deep-seated tumours and 70 MHz for deep-seated tumours. Phase and amplitude control allows focusing of electromagnetic energy (EM) to deep-seated tumours. The specific absorption rate (SAR) dose distribution can be modified to achieve uniform heating of tumours with complex shapes and heterogeneous tissue properties. A lithium fluoride thermoluminescent dosimeter (TLD) in a flexible film cassette has been developed for real-time dose measurement. Results: Four types of 434 MHz applicators were manufactured with 3, 4, 9 or 12 independent applicators. Two types of 70 MHz applicators were made with 4 or 6 independent applicators. Phantom tests demonstrated the ability to control the SAR pattern by phase and amplitude control. Placement of the dosimeter between bolus and phantom increased the phantom surface temperature up to 3 °C and showed that the ratio of absorbed energy in TLD to dose in water approaches (0.83 ± 3%) for photon energies >60 keV. Conclusions: Simultaneous and controlled radiation and local hyperthermia is technically feasible in a preclinical setting, a clinical feasibility test is the next step. © 2015 Informa UK Ltd. All rights reserved.

Development of lithium CPS based limiters for realization of a concept of closed lithium circulation loop in Tokamak / Zharkov,M.Yu. / Physics Procedia. - 2015.

Annotation:

Cooling of tokamak boundary plasma owing to radiation of non-fully stripped lithium ions is considered as a promising way for protection of plasma facing elements (PFE) in tokamak. It may be effectively realized when the main part of lithium ions are involved in the closed circuit of migration between plasma and PFE surface. Such an approach may be implemented with the use of lithium device whose hot (500-600 °C) area to be effected by plasma serves as a Li-emitter and the cold part (∼180 °C) as a Li-collector in the shadow. Capillary-pore system (CPS) provides the returning of collected and condensed lithium to emitting zone by capillary forces. The main goals of the last T-11M lithium experiments were investigating Li ions transport in the tokamak scrape of layer (SOL) and their collecting by different kinds of limiters. The design of devices based on lithium CPS with different ratio of emitting/collecting area is the main subject of this paper. © 2015 The Authors.

Di-hadron correlations with identified leading hadrons in 200 GeV Au+Au and d+Au collisions at STAR / Adamczyk,L. / Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 2015.

Annotation:

The STAR Collaboration presents for the first time two-dimensional di-hadron correlations with identified leading hadrons in 200 GeV central Au. +. Au and minimum-bias d. +. Au collisions to explore hadronization mechanisms in the quark gluon plasma. The enhancement of the jet-like yield for leading pions in Au. +. Au data with respect to the d. +. Au reference and the absence of such an enhancement for leading non-pions (protons and kaons) are discussed within the context of a quark recombination scenario. The correlated yield at large angles, specifically in the ridge region, is found to be significantly higher for leading non-pions than pions. The consistencies of the constituent quark scaling, azimuthal harmonic model and a mini-jet modification model description of the data are tested, providing further constraints on hadronization. © 2015 The Authors.

Difference of magnetic pulse compaction from traditional uniaxial pressing of alumina nanopowders / Zholnin,A. / Physics Procedia. - 2015.

Annotation:

Processes of pressureless sintering of alumina nanopowders, subjected to traditional uniaxial pressing or magnetic pulse compaction, were investigated with the use of X-ray diffraction, scanning electron microscopy, thermal analysis and dilatometry. In this study sintering mechanisms, initiated by magnetic-pulse compacting and absent in the classical compaction, for the first time were found. © 2015 Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license.

Differential top-antitop cross-section measurements as a function of observables constructed from final-state particles using pp collisions at root s=7 TeV in the ATLAS detector / Aad,G / JOURNAL OF HIGH ENERGY PHYSICS. - 2015

Annotation:

Various differential cross-sections are measured in top-quark pair (t (t) over bar) events produced in proton-proton collisions at a centre-of-mass energy of root s = 7 TeV at the LHC with the ATLAS detector. These differential cross-sections are presented in a data set corresponding to an integrated luminosity of 4.6 fb(-1). The differential cross-sections are presented in terms of kinematic variables, such as momentum, rapidity and invariant mass, of a top-quark proxy referred to as the pseudo-top-quark as well as the pseudo-top-quark pair system. The dependence of the measurement on theoretical models is minimal. The measurements are performed on tt events in the lepton+jets channel, requiring exactly one charged lepton and at least four jets with at least two of them tagged as originating from a b-quark. The hadronic and leptonic pseudo-top-quarks are defined via the leptonic or hadronic decay mode of the W boson produced by the top-quark decay in events with a single charged lepton. Differential cross-section measurements of the pseudo-top-quark variables are compared with several Monte Carlo models that implement next-to-leading order or leading-order multi-leg matrix-element calculations.

Diffusion of hygrogen in dislocations elastic fields in iron / Sivak,A.B. / Problems of Atomic Science and Technology, Series Thermonuclear Fusion. - 2015.

Annotation:

The effect of dislocations stress fields on their sinks efficiencies for hydrogen interstitial atoms has been studied for temperatures 293 and 600 K and dislocation density 31014 m-2 in BCC iron crystal. Straight full screw and edge dislocations in basic slip systems 111110, 111112, 100100, 100110 have been considered. Diffusion of defects has been simulated by object kinetic Monte Carlo method. Interaction energies of defects with dislocations have been calculated within the anisotropic theory of elasticity. Elastic fields of dislocations change the sink efficiency of not more than 25% of the non-interacting linear sink efficiency at room tem-perature. Elastic fields of edge dislocations increase the dislocations sink efficiency, and the elastic fields of screw ones either decrease (in the case of dislocations with = 111 Burgers vector), or do not change (in the case of dislocations with 100 Burgers vector). At temperatures above 600 K, dislocations mainly influence the behavior of hydrogen in bcc iron due to the large binding energy of the hydrogen atom with dislocation cores.

Direct Search for Dark Matter with DarkSide / Agnes,P / 7TH INTERNATIONAL SYMPOSIUM ON LARGE TPCS FOR LOW-ENERGY RARE EVENT DETECTION. - 2015.

Annotation:

The DarkSide experiment is designed for the direct detection of Dark Matter with a double phase liquid Argon TPC operating underground at Laboratori Nazionali del Gran Sasso. The TPC is placed inside a 30 tons liquid organic scintillator sphere, acting as a neutron veto, which is in turn installed inside a 1 kt water Cherenkov detector. The current detector is running since November 2013 with a 50 kg atmospheric Argon fill and we report here the first null results of a Dark Matter search for a (1422 +/- 67) kg.d exposure. This result correspond to a 90% CL upper limit on the WIMP-nucleon cross section of 6.1 x10(-44) cm(2) (for a WIMP mass of 100 GeV/c(2)) and it's currently the most sensitive limit obtained with an Argon target.

Directed flow in relativistic heavy-ion collisions within the PHSD transport approach and 3FD hydrodynamical model / Konchakovski,VP / HOT QUARKS 2014: WORKSHOP FOR YOUNG SCIENTISTS ON THE PHYSICS OF ULTRARELATIVISTIC NUCLEUS-NUCLEUS COLLISIONS. - 2015.

Annotation:

We analyze recent STAR data for the directed flow of protons, antiprotons and charged pions obtained within the beam energy scan program within the Parton-Hadron-StringDynamics (PHSD) transport model and the 3-Fluid hydroDynamics (3FD) approach. We clarify the role of partonic degrees of freedom in the kinetic PHSD approach. The PHSD results, simulating a partonic phase and its coexistence with a hadronic one, are roughly consistent with data. The hydrodynamic results are obtained for two EoS, a pure hadronic EoS and an EoS with a crossover type transition. The latter case is favored by the STAR experimental data. Special attention is paid to the description of antiproton directed flow based on the balance of pp annihilation and the inverse processes for Np pair creation from multi-meson interactions. Generally, a semi-qualitative agreement between the measured data and model results supports the idea of a crossover type quark-hadron transition which softens the nuclear EoS.

Distributions of topological observables in inclusive three- and four-jet events in pp collisions at root s=7 TeV / Khachatryan,V / EUROPEAN PHYSICAL JOURNAL C. - 2015.

Annotation:

This paper presents distributions of topological observables in inclusive three- and four-jet events produced in pp collisions at a centre-of-mass energy of 7 TeV with a data sample collected by the CMS experiment corresponding to a luminosity of 5.1 fb(-1). The distributions are corrected for detector effects, and compared with several event generators based on two- and multi-parton matrix elements at leading order. Among the considered calculations, MadGraph interfaced with PYTHIA6 displays the overall best agreement with data.

Dmitrenko,A.V. Analytical Estimation of Velocity and Temperature Fields in a Circular Pipe on the Basis of Stochastic Equations and Equivalence of Measures / Dmitrenko,A.V. // Journal of Engineering Physics and Thermophysics. - 2015.

Annotation:

A stream of nonisothermalNewtonian liquid in a circular smooth pipe is considered on the basis of systems of stochastic equations and of the physical law of equivalence of measures between laminar and turbulent motions. Analytical expressions were previously obtained for isothermal flows for the first and second critical Reynolds numbers, critical point, indices of velocity profiles, second-order correlation moments, correlation functions, and spectral functions depending on the parameters of initial turbulence. Analytical expressions, obtained with the use of the earlier derived formulas for the critical Reynolds numbers and the critical points, are presented for the indices of velocity and temperature profiles as functions of the initial turbulence parameters as well as of the Eckert and Prandtl numbers. © 2015 Springer Science+Business Media New York

Dokuchaev,V.I. Spin and mass of the supermassive black hole in the Galactic Center / Dokuchaev,V.I. / Physics of Atomic Nuclei. - 2015.

Annotation:

A new method for exact determination of the masses and spins of black holes from the observations of quasi-periodic oscillations is discussed. The detected signal from the hot clumps in the accretion plasma must contain modulations with two characteristic frequencies: the frequency of rotation of the black hole event horizon and the frequency of the latitudinal precession of the clump’s orbit. Application of the method of two characteristic frequencies for interpretation of the observed quasi-periodic oscillations from the supermassive black hole in the Galactic center in the X-rays and in the near IR region yields the most exact, for the present, values of the mass and the spin (Kerr parameter) of the Sgr A* black hole: M = (4.2 ± 0.2) × 10sup6/supM⊙ and a = 0.65 ± 0.05. The observed quasi-periodic oscillations with a period of about 11.5 min are identified as the black hole event horizon rotation period and those with a period of about 19 min are identified as the latitudinal oscillation period of the hot spot orbits in the accretion disk. © 2015, Pleiades Publishing, Ltd.

Double electron capture of Cd-106 in the TGV-2 experiment / Rukhadze,NI / WORKSHOP ON CALCULATION OF DOUBLE-BETA-DECAY MATRIX ELEMENTS (MEDEX15). - 2015.

Annotation:

A new experimental run of searching for EC/EC decay of Cd-106 was performed at the Modane underground laboratory (4800 m w.e.) using the TGV-2 spectrometer and similar to 23.2 g Cd-106 with enrichment of 99.57%. The limit on 2 nu EC/EC decay of Cd-106 -T-1/2(2 nu EC/EC) 3.1x10(20) y, at 90% C. L was obtained from the preliminary calculation of experimental data accumulated for 7018 h of measurement. The limits on the resonance neutrino-less double electron capture decay of Cd-106 were obtained from the measurement of similar to 23.2 g of Cd-106 with the low-background HPGe spectrometer OBELIX lasted 395 h -T-1/2(KL, 2741 keV) 0.9x10(20) y and T-1/2(KK, 2718 keV) 1.4x10(20) y at 90% C.L.

Dremin,I.M. Interaction region of high energy protons / Dremin,I.M. / Physics-Uspekhi. - 2015.

Annotation:

New proton-proton collision data from theLHC have considerably extended the energy range over which the structure of the proton-proton interaction region can be studied. In this paper, we combine the unitarity relation with experimental data on elastic scattering in the diffraction cone to show how the shape and the darkness of the inelastic interaction region of colliding protons change with increasing the proton energy. In particular, at LHC energies, small-impact-parameter collisions become fully absorptive, with some implications for inelastic processes as well. The possibility of changing from the blackcore scenario at LHC energies to the fully transparent scenario at higher energies is discussed-a phenomenon that implies changing from the black disk to black toroid terminology. As the asymptotic behavior is approached, a different regime may arise. The parameter determining the opacity of central collisions also crucially affects the differential cross section of elastic scattering outside the diffraction cone, where all phenomenological models fail for the LHC energies. It is in this region where the ratio of the real to imaginary part of the elastic scattering amplitude in nonforward scattering becomes a decisive factor, as indeed it should according to the unitarity condition. Our results make it possible for the first time to estimate this ratio outside the diffraction cone by comparing with data for LHC energies, and it turns out to be drastically different from the values measured at forward scattering. Moreover, both real and imaginary parts are found to behave differently in different phenomenological models and in the approach based on the unitarity condition. This problem is still to be resolved. All the conclusions are made solely in the framework of the indubitable unitarity condition using experimental data on elastic proton scattering in the diffraction cone, without resorting to other theoretical methods, such as quantum chromodynamics or phenomenological models. © 2015 Uspekhi Fizicheskikh Nauk, Russian Academy of Sciences.

Dremin,I.M. Robust impact parameter profile of inelastic collisions / Dremin,I.M. / JETP Letters. - 2015.

Annotation:

It is shown that the impact parameter profile of inelastic hadron collisions is robust to admissible variations of the shape of the diffraction cone of elastic scattering. This conclusion is obtained using the unitarity condition and experimental data only with no phenomenological model inputs.

Dremin,I.M. Torus or black disk? / Dremin,I.M. / Bulletin of the Lebedev Physics Institute. - 2015.

Annotation:

It is shown that the interaction region of colliding protons appears almost totally absorbing (black) at impact parameters to 0.4–0.5 fm and LHC energy of 7 TeV. The blackness of the proton interaction region for central interactions is completely defined by the ratio of the diffraction cone slope B in elastic scattering to the total cross section. The corresponding parameter is close to unity at LHC energies. The behavior of this ratio at higher energies will determine whether the interaction region structure will remind a torus or a black disk. Recent phenomenological fittings of experimental data at 7 TeV give no way of distinguishing these cases due to inaccuracies of experiments and uncertainties of the extrapolation to unmeasured regions of transferred momenta.

Dremin,IM The Profile of Inelastic Collisions from Elastic Scattering Data / Dremin,IM / ADVANCES IN HIGH ENERGY PHYSICS. - 2015.

Annotation:

Using the unitarity relation in combination with experimental data about the elastic scattering in the diffraction cone, it is shown how the shape and the darkness of the inelastic interaction region of colliding protons change with increase of their energies. In particular, the collisions become fully absorptive at small impact parameters at LHC energies that results in some special features of inelastic processes. Possible evolution of this shape with the dark core at the LHC to the fully transparent one at higher energies is discussed that implies that the terminology of the black disk would be replaced by the black toroid. The approach to asymptotics is disputed. The ratio of the real to imaginary parts of the nonforward elastic scattering amplitude is briefly discussed. All the conclusions are only obtained in the framework of the indubitable unitarity condition using experimental data about the elastic scattering of protons in the diffraction cone without any reference to quantum chromodynamics (QCD) or phenomenological approaches.

Dubinov,A.E. Dichromatic Langmuir waves in degenerate quantum plasma / Dubinov,A.E., Kitayev,I.N. / Plasma Physics Reports. - 2015.

Annotation:

Langmuir waves in fully degenerate quantum plasma are considered. It is shown that, in the linear approximation, Langmuir waves are always dichromatic. The low-frequency component of the waves corresponds to classical Langmuir waves, while the high-frequency component, to free-electron quantum oscillations. The nonlinear problem on the profile of dichromatic Langmuir waves is solved. Solutions in the form of a superposition of waves and in the form of beatings of its components are obtained. © 2015, Pleiades Publishing, Ltd.

Dymnikova,Irina Regular black hole remnants and graviatoms with de Sitter interior as heavy dark matter candidates probing inhomogeneity of early universe / Dymnikova,Irina, Khlopov,Maxim / INTERNATIONAL JOURNAL OF MODERN PHYSICS D. - 2015.

Annotation:

We address the question of regular primordial black holes with de Sitter interior, their remnants and gravitational vacuum solitons G-lumps as heavy dark matter candidates providing signatures for inhomogeneity of early universe, which is severely constrained by the condition that the contribution of these objects in the modern density does not exceed the total density of dark matter. Primordial black holes and their remnants seem to be most elusive among dark matter candidates. However, we reveal a nontrivial property of compact objects with de Sitter interior to induce proton decay or decay of neutrons in neutron stars. The point is that they can form graviatoms, binding electrically charged particles. Their observational signatures as dark matter candidates provide also signatures for inhomogeneity of the early universe. In graviatoms, the cross-section of the induced proton decay is strongly enhanced, what provides the possibility of their experimental searches. We predict proton decay paths induced by graviatoms in the matter as an observational signature for heavy dark matter searches at the IceCUBE experiment.

Dynamics of interacting quintessence / Shahalam,M. / European Physical Journal C. - 2015.

Annotation:

In this paper, we investigate coupled quintessence with scaling potential assuming specific forms of the coupling as A namely, (Formula presented.) and (Formula presented.), and present phase space analysis for three different interacting models. We focus on the attractor solutions that can give rise to late time acceleration with (Formula presented.) of order unity in order to alleviate the coincidence problem. © 2015, The Author(s).

Early processes in positron and positronium chemistry: possible scavenging of epithermal e(+) by nitrate ion in aqueous solutions / Byakov,VsevolodM / 11TH INTERNATIONAL WORKSHOP ON POSITRON AND POSITRONIUM CHEMISTRY (PPC-11). - 2015.

Annotation:

Positron ionization slowing down, formation of the positron track, reactions of e(+) with track species and its interaction with a scavenger on a subpicosecond timescale, including the process of the positronium formation process are discussed. Interpretation of the positron annihilation lifetime data on positronium formation in aqueous solutions of NO3- anions, known as efficient scavengers of the presolvated track electrons, suggests that these ions may also capture epithermal (presolvated) positrons as well.

EAS array of the NEVOD Experimental Complex / Chiavassa,A. / Journal of Physics: Conference Series. - 2015.

Annotation:

A new setup for registration of the electromagnetic component of the EAS at the "knee" region of the energy spectrum of primary cosmic rays (PCR) is now under construction on the basis of the experimental complex NEVOD-DECOR (Moscow, Russia). The EAS array detecting system has a cluster organization. Clusters are located in the MEPhI campus. The specific features of the array registering system that provides particle detection, data acquisition, cluster synchronization and events selection are discussed. The results of counter characteristics study are also presented. © Published under licence by IOP Publishing Ltd.

Effect of annealing on structural and optical properties of Cu2ZnSnS4 thin films grown by pulsed laser deposition / Medvedeva,SS / THIN SOLID FILMS. - 2015.

Annotation:

In this work, we compare the effect of different types of thermal annealing on the morphological, structural and optical properties of Cu2ZnSnS4 (CZTS) thin films grown by reactive Pulsed Laser Deposition in H2S flow. Rutherford backscattering spectrometry, atomic force microscopy, X-ray diffraction, Raman spectroscopy and optical spectrophotometry data reveal dramatic increase of the band gap and the crystallite size without the formation of secondary phases upon annealing in N-2 at the optimized conditions. (C) 2015 Elsevier B.V. All rights reserved.

Effect of event selection on jetlike correlation measurement in d + Au collisions at √sNN = 200 GeV / Adamczyk,L. / Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 2015.

Annotation:

Dihadron correlations are analyzed in √sNN = 200 GeV d + Au collisions classified by forward charged particle multiplicity and zero-degree neutral energy in the Au-beam direction. It is found that the jetlike correlated yield increases with the event multiplicity. After taking into account this dependence, the non-jet contribution on the away side is minimal, leaving little room for a back-to-back ridge in these collisions. © 2015 The Authors.

Effect of interlayer macrostress on hydride orientation in shell tubes from Zr-based alloys / Isaenkova,M. / IOP Conference Series: Materials Science and Engineering. - 2015.

Annotation:

Methods of texture analysis allowed to show that inhomogeneity of the crystallographic texture in shell tube wall is responsible for rise of tangential macrostress in the tube. This inhomogeneity predetermines a difference of thermal expansion between outside and inside layers of tube at its exploitation temperature. The indicator of such stress is formation of radially-oriented hydrides in the transverse section of tube, subjected to treatment in autoclave. © Published under licence by IOP Publishing Ltd.

Effect of water subcooling to the saturation temperature on boiling crisis characteristics during a rapid increase in the heat release power / Delov,M.I./ Bulletin of the Lebedev Physics Institute. - 2015.

Annotation:

The experimental results on the effect of water subcooling to the saturation temperature and the thermal exposure time on the maximum allowed energy removed by coolant without the boiling crisis onset are presented. The boiling crisis under subcooling conditions results in cooled surface damage. The results of this study can find application to calculate cooling systems of equipment operating in pulsed mode. © 2015, Allerton Press, Inc.

Electric pulse consolidation of tantalum anodes for electrolytic capacitors / Yurlova,M.S. / Inorganic Materials: Applied Research. - 2015.

Annotation:

The structure of tantalum powders is investigated and the possibility for their application as anodes of electrolytic capacitors is studied. Critical parameters of the electric pulse consolidation (EPC) of powders making it possible to get a homogeneous volume distribution of pores are determined. The effect of the compacting pressure and the density of current through the powder on the porous structure and the specific surface of anodes of capacitor tantalum powders of classes I–IV is ascertained. The specific surface of anodes compacted by EPC is found to be higher by 18–230% than for anodes made by the conventional technology. © 2015, Pleiades Publishing, Ltd.

Electromagnetic shields based on multilayer film structures / Grabchikov,S.S. / Bulletin of the Lebedev Physics Institute. - 2015.

Annotation:

Electrodeposited multilayer-film electromagnetic shields are very promising for protecting various devices due to high shielding efficiency and the possibility of depositing on complex-shaped objects. In this communication, we present the results of measurements of the shielding efficiency of such shields. The shields represent alternating layers of materials with high magnetic permeability (Ni-Fe) and high conductivity (Cu). The maximum number of double layers is 45. It is shown that the shielding efficiency in the weak magnetic fields (0.1–0.2 mT) is 8–10; at higher magnetic field strengths (1.5–2.5 mT), it reaches 80–100. It is shown that the shielding factor increases with the number of layers in the shield at the same thickness of a soft magnetic material. A permalloy shield at the same amount of a soft magnetic material has an efficiency lower by a factor of 3–15 depending on the magnetic field strength.

Elliptic flow of identified hadrons in Pb-Pb collisions at root(NN)-N-s=2.76 Tev / Abelev,B / JOURNAL OF HIGH ENERGY PHYSICS. - 2015

Annotation:

The elliptic flow coefficient (v(2)) of identified particles in Pb-Pb collisions at root s(NN) = 2.76 TeV was measured with the ALICE detector at the Large Hadron Collider (LHC). The results were obtained with the Scalar Product method, a two-particle correlation technique, using a pseudo-rapidity gap of |Delta eta| 0.9 between the identified hadron under study and the reference particles. The v (2) is reported for pi(+/-), K-+/-, K-S(0), p+(p) over bar, phi, Lambda+(Lambda) over bar, Xi+(Xi) over bar (+) and Omega(-)+(Omega) over bar (+) in several collision centralities. In the low transverse momentum (p(T)) region, p(T) 3 GeV/c, v(2)(p(T)) exhibits a particle mass dependence consistent with elliptic flow accompanied by the transverse radial expansion of the system with a common velocity field. The experimental data for pi (+/-) and the combined K-+/- and K-S(0) results, are described fairly well by hydrodynamic calculations coupled to a hadronic cascade model (VISHNU) for central collisions. However, the same calculations fail to reproduce the v(2)(p(T)) for p+(p) over bar, phi, Lambda+(Lambda) over bar, Xi+(Xi) over bar (+). For transverse momentum values larger than about 3 GeV/c, particles tend to group according to their type, i.e. mesons and baryons. The present measurements exhibit deviations from the number of constituent quark (NCQ) scaling at the level of +/- 20% for p(T) 3 GeV/c.

Elmanov,G.N. Crystallization process of nickel-based amorphous alloys / Elmanov,G.N., Ivanitskaya,E.A., Zharikov,E.S. / Non-ferrous Metals. - 2015.

Annotation:

The subject of research includes the structure and phase transformations during a multistage crystallization of amorphous alloys with composition of Niinf71.5/infCrinf6.8/infFeinf2.7/infBinf11.9/infSiinf7.1/inf and Niinf63.4/infCrinf7.4/infFeinf4.3/inf?ninf0.8/infBinf15.6/infSiinf8.5/inf alloys (AWS BNi-2, according to American Welding Society). Amorphous alloys were obtained in the form of tapes (0.04-0.05 mm thickness) by rapid solidification (rapid quenching) techniques. The changes in structure, phase composition and topology of amorphous alloys, surface were investigated after different crystallization stages at the temperature range of 450-650 °?, using differential thermal analysis, X-ray diffraction analysis, atomic force microscopy, scanning electron microscopy and energy-dispersive X-ray microanalysis. The sequence of crystalline phases, formation was defined together with their crystal structure, peculiarities of microstructure and nature of chemical elements, redistribution during crystallization of these amorphous alloys. According to this, the surface topology changes adequately reflect the process, occurring during crystallization. The α-Ni solid solution crystals (80-100 nm diameter) are formed in amorphous matrix at initial crystallization stage at the temperature range of 450-500 °?. The biggest part of boron in this solution is displaced on crystal boundaries and amorphous phase. At the second stage (500-550 °C), amorphous phase is crystallized with formation of fine metastable τ-phase with ?inf23/infBinf6/inf crystal structure, which covers the entire surface of the sample with gradual grow. In the third crystallization stage (more than 550-600 °C), τ-phase is decomposed simultaneously into boride with Niinf3/infB-type structure and lowtemperature modification of βinf1/inf-Niinf3/infSi silicide. The first and second phases are characterized by low content of silicon and boron, respectively. There was made an offer to use a decomposition mechanism of metastable τ-phase, formed at intermediate crystallization stage. When temperatures are close to solidus, monoboride separation (Cr, Ni, Fe)B with high chromium content, which amount is increased with increasing of annealing temperature, occurs in alloys under study. Monoboride was observed by scanning electron microscopy, but not by X-ray diffraction method. © G. N. Elmanov, E. A. Ivanitskaya, E. S. Zharikov, 2015.

Elokhin,A.P. Unconventional Methods of Radiological Environmental Monitoring and Earthquake Prediction / Elokhin,A.P. / Atomic Energy. - 2015.

Annotation:

Methods: of radiological monitoring of the environment that can be used on objects utilizing atomic energy, including NPP, are examined. The methods are based on the indications of sensors measuring the dose rate and the spectral characteristics of photon radiation. The sensors can be placed in the opening of a vent stack as well as on unmanned radio-controlled aircraft and underwater apparatus. Radiological monitoring is accomplished in real-time by transmitting information along a radio channel to the pilot’s and dosimetrist’s consoles. A method of remote radiological monitoring where the diagnostics apparatus is a radar station operating in a definite wavelength range is briefly described. The use of cryogenic technologies for recycling radioactive inert gases discharged into the atmosphere is briefly described.

Energetic, crystallographic and diffusion characteristics of hydrogen isotopes in iron / Sivak,A.B. / Journal of Nuclear Materials. - 2015.

Annotation:

Abstract Energetic, crystallographic and diffusion characteristics of various interstitial configurations of H atoms and their complexes with self-point defects (SIA - self-interstitial atom, V - vacancy) in bcc iron have been calculated by molecular statics and molecular dynamics using Fe-H interatomic interaction potential developed by Ramasubramaniam et al. (2009) and modified by the authors of the present work and Fe-Fe matrix potential M07 developed by Malerba et al. (2010). The most energetically favorable configuration of an interstitial H atom is tetrahedral configuration. The energy barrier for H atom migration is 0.04 eV. The highest binding energy of all the considered complexes "vacancy - H atom" and "SIA - H atom" is 0.54 and 0.15 eV, respectively. The binding energy of H atom with edge dislocations in slip systems 〈1 1 1〉1 1 0, 〈1 1 1〉1 1 2, 〈1 0 0〉1 0 0, 〈1 0 0〉1 1 0 is 0.32, 0.30, 0.45, 0.54 eV, respectively. The binding energy of H atom in VHn complexes (n = 1 ... 15) decreases from 0.54 to 0.35 eV with increasing of n from 1 to 6. At n > 6, it decreases to ∼0.1 eV. The temperature dependences of hydrogen isotopes (P, D, T) diffusivities have been calculated for the temperature range 70-1800 K. Arrhenius-type dependencies describe the calculated data at temperatures T < 100 K. At T > 250 K, the temperature dependencies of the diffusivities DP, DD, DT have a parabolic form. The diffusivities of H isotopes are within 10% at room temperature. The isotope effect becomes stronger at higher temperatures, e.g., ratios DP/DD and DP/DT at 1800 K equal 1.23 and 1.40, respectively. © 2015 Elsevier B.V. All rights reserved.

Energy Characteristics of Forbush Decreases for Different Types of Heliospheric Disturbances According to Muon Hodoscope URAGAN / Yakovleva,E.I. / Physics Procedia. - 2015.

Annotation:

Experimentally obtained energy characteristics of the muon flux during Forbush decreases registered by means of the muon hodoscope URAGAN at different phases of 23rd and 24th solar cycles are studied. To obtain the energy spectra of Forbush decrease amplitudes in the flux of the primary particles, coupling functions of the primary and the secondary cosmic ray fluxes for five zenith-angular intervals of the muon hodoscope URAGAN were used. It is shown that the energy characteristics of Forbush decreases, caused by heliospheric disturbances of different types, significantly differ on phases of maximum and minimum of the solar cycle. © 2015 The Authors.

Energy dependence of acceptance-corrected dielectron excess mass spectrum at mid-rapidity in Au+Au collisions at √sNN=19.6 and 200 GeV / Adamczyk,L. / Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 2015.

Annotation:

The acceptance-corrected dielectron excess mass spectra, where the known hadronic sources have been subtracted from the inclusive dielectron mass spectra, are reported for the first time at mid-rapidity |yee|<1 in minimum-bias Au+Au collisions at √sNN=19.6 and 200 GeV. The excess mass spectra are consistently described by a model calculation with a broadened ρ spectral function for Mee<1.1 GeV/c2. The integrated dielectron excess yield at √sNN=19.6 GeV for 0.4<Mee<0.75 GeV/c2, normalized to the charged particle multiplicity at mid-rapidity, has a value similar to that in In+In collisions at √sNN=17.3 GeV. For √sNN=200 GeV, the normalized excess yield in central collisions is higher than that at √sNN=17.3 GeV and increases from peripheral to central collisions. These measurements indicate that the lifetime of the hot, dense medium created in central Au+Au collisions at √sNN=200 GeV is longer than those in peripheral collisions and at lower energies. © 2015 The Authors.

Energy dependence of K pi, p pi, and Kp fluctuations in Au plus Au collisions from root s(NN)=7.7 to 200 GeV / Adamczyk,L / PHYSICAL REVIEW C. - 2015.

Annotation:

A search for the quantum chromodynamics (QCD) critical point was performed by the STAR experiment at the BNL Relativistic Heavy Ion Collider, using dynamical fluctuations of unlike particle pairs. Heavy ion collisions were studied over a large range of collision energies with homogeneous acceptance and excellent particle identification, covering a significant range in the QCD phase diagram where a critical point may be located. Dynamical K pi, p pi, and Kp fluctuations as measured by the STAR experiment in central 0-5% Au + Au collisions from center-of-mass collision energies root s(NN) = 7.7 to 200 GeV are presented. The observable nu(dyn) was used to quantify the magnitude of the dynamical fluctuations in event-by-event measurements of the Kp, pp, and Kp pairs. The energy dependences of these fluctuations from central 0-5% Au + Au collisions all demonstrate a smooth evolution with collision energy.

Energy deposit spectrum of the EAS electromagnetic component at the PRISMA-32 array / Volchenko,V.I. / Bulletin of the Russian Academy of Sciences: Physics. - 2015.

Annotation:

The results from a 29-month investigation into the EAS electromagnetic component using the PRISMA-32 array are presented, notably for the central density spectrum and energy deposit spectrum. The array consists of 32 en-detectors in which specialized inorganic scintillators (SL6-5 phosphorus composition) based on silver-activated zinc sulfide (ZnS) with LiF enriched to 90% 6Li (ZnS(Ag) + 6LiF) are used as detecting layers. The possibility of detecting the electromagnetic component using a thin scintillation neutron detector with the multiple passage of charged particles is shown. The experimental data are compared to the results from simulations. © 2015, Allerton Press, Inc.

Eroshenko,Y.N. Physical laboratory at the center of the Galaxy / Eroshenko,Y.N., Dokuchaev,V.I. / Physics-Uspekhi. - 2015.

Annotation:

We review the physical processes that occur at the center of the Galaxy and that are related to the supermassive black hole SgrA∗ residing there. The discovery of high-velocity S0 stars orbiting SgrA∗ for the first time allowed measuring the mass of this supermassive black hole, the closest one to us, with a 10% accuracy, with the result Mh = (4.1 ± 0.4) × 10sup6/supM⊙. Further monitoring can potentially discover the Newtonian precession of the S0 star orbits in the gravitational field of the black hole due to invisible distributed matter. This will yield the 'weight' of the elusive dark matter concentrated there and provide new information for the identification of dark matter particles. The weak accretion activity of the 'dormant quasar' at the galactic center occasionally shows up as quasiperiodic X-ray and near-IR oscillations with mean periods of 11 and 19 min. These oscillations can possibly be interpreted as related to the rotation frequency of the SgrA∗ event horizon and to the latitude oscillations of hot plasma spots in the accretion disk. Both these frequencies depend only on the black hole gravitational field and not on the accretion model. Using this interpretation yields quite accurate values for both the mass Mh and the spin a (Kerr rotation parameter) of SgrA∗: Mh = (4.2 ± 0.2) × 10sup6/supM⊙ and a = 0.65 ± 0.05. © 2015 Uspekhi Fizicheskikh Nauk, Russian Academy of Sciences.

Eroshenko,Y.N. Precession of Fast S0 Stars in the Vicinity of Supermassive Black Hole in the Galactic Center / Eroshenko,Y.N., Klimkov,K.S., Dokuchaev,V.I. // Physics Procedia. - 2015.

Annotation:

We elaborate the model of the influence of the diffuse dark matter, invisible stars or stellar mass black holes on the motion of the observed fast moving S0 stars [1-4] around the supermassive black hole SgrA∗in the Galactic center with a mass MBH = 4·106. We will call all this invisible mass as a dark matter. The additional mass perturbs the elliptical orbits of the S0 mass resulting in the so called Newtonian precession of the elliptical orbits. The major aim of our research is the fitting of the published dates on the observed orbital positions of the S0 stars by the theoretically modeling orbit with a power-law profile of the additional (dark matter) mass. Nowadays the observational data provide only the upper limit on the additional mass. In the nearest years the observations of the S0 stars may provide the real weighing of the dark matter inside the orbits of these S0 stars in the Galactic center. This method is a very perspective for the elucidation of the formation and evolution of the dark matter in the Galactic nucleus. © 2015 The Authors.

Eroshenko,Y.N. Quantum electron levels in the field of a charged black hole / Eroshenko,Y.N., Dokuchaev,V.I. / Physics of Atomic Nuclei. - 2015.

Annotation:

Stationary solutions of the Dirac equation in the metric of the charged Reissner–Nordstrom black hole are found. In the case of an extremal black hole, the normalization integral of the wave functions is finite, and the regular stationary solution is physically self-consistent. The presence of quantum electron levels under the Cauchy horizon can have an impact on the final stage of the Hawking evaporation of the black hole, as well as on the particle scattering in the field of the black hole. © 2015, Pleiades Publishing, Ltd.

Eroshenko,Y.N. Weighing of the dark matter at the center of the galaxy / Eroshenko,Y.N., Dokuchaev,V.I. / JETP Letters. - 2015.

Annotation:

A promising method for measuring the total mass of the dark matter near a supermassive black hole at the center of the Galaxy based on observations of nonrelativistic precession of the orbits of fast S0 stars together with constraints on the annihilation signal from the dark matter particles has been discussed. An analytical expression for the precession angle has been obtained under the assumption of a power-law profile of the dark matter density. In the near future, modern telescopes will be able to measure the precession of the orbits of S0 stars or to obtain a strong bound on it. The mass of the dark matter necessary for the explanation of the observed excess of gamma radiation owing to the annihilation of the dark matter particles has been calculated with allowance for the Sommerfeld effect. © 2015, Pleiades Publishing, Inc.

Eroshenko,Y.N. Weighing of the dark matter at the center of the galaxy / Eroshenko,Y.N., Dokuchaev,V.I. / JETP Letters. - 2015.

Annotation:

A promising method for measuring the total mass of the dark matter near a supermassive black hole at the center of the Galaxy based on observations of nonrelativistic precession of the orbits of fast S0 stars together with constraints on the annihilation signal from the dark matter particles has been discussed. An analytical expression for the precession angle has been obtained under the assumption of a power-law profile of the dark matter density. In the near future, modern telescopes will be able to measure the precession of the orbits of S0 stars or to obtain a strong bound on it. The mass of the dark matter necessary for the explanation of the observed excess of gamma radiation owing to the annihilation of the dark matter particles has been calculated with allowance for the Sommerfeld effect. © 2015, Pleiades Publishing, Inc.

Evidence for the decay B-0 - eta pi(0) / Pal,B / PHYSICAL REVIEW D. - 2015.

Annotation:

We report a search for the charmless hadronic decay B-0 - eta pi(0) with a data sample corresponding to an integrated luminosity of 694 fb(-1) containing 753 x 10(6) BB pairs. The data were collected by the Belle experiment running on the Upsilon(4S) resonance at the KEKB e(+)e(-) collider. We measure a branching fraction B(B-0 eta pi(0)) = (4.1(-1.5-0.7)(+1.75+0.5)) x 10(-7), where the first unceminty is statistical and the second is systematic. Our measurement gives an upper limit of beta(B-0 - n pi(0)) 6.5 x 10(-7) at 90% confidence level. The signal has a significance of 3.0 standard deviations and constitutes the first evidence for this decay mode.

Evidence for the Higgs-boson Yukawa coupling to tau leptons with the ATLAS detector / TheATLAScollaboration / Journal of High Energy Physics. - 2015.

Annotation:

Abstract: Results of a search for H → ττ decays are presented, based on the full set of proton-proton collision data recorded by the ATLAS experiment at the LHC during 2011 and 2012. The data correspond to integrated luminosities of 4.5 fbsup−1/sup and 20.3 fbsup−1/sup at centre-of-mass energies of √s = 7 TeV and √s = 8 TeV respectively. All combinations of leptonic (τ→ℓνν¯ with ℓ = e, μ) and hadronic (τ → hadrons ν) tau decays are considered. An excess of events over the expected background from other Standard Model processes is found with an observed (expected) significance of 4.5 (3.4) standard deviations. This excess provides evidence for the direct coupling of the recently discovered Higgs boson to fermions. The measured signal strength, normalised to the Standard Model expectation, of μ = 1. 43inf− 0.37/inf; sup+ 0.43/sup is consistent with the predicted Yukawa coupling strength in the Standard Model.[Figure not available: see fulltext.] © 2015, The Author(s).

Evidence of W gamma gamma Production in pp Collisions at root s=8 TeV and Limits on Anomalous Quartic Gauge Couplings with the ATLAS Detector / Aad,G / PHYSICAL REVIEW LETTERS. - 2015.

Annotation:

This Letter reports evidence of triple gauge boson production pp - W(l nu)gamma gamma + X, which is accessible for the first time with the 8 TeV LHC data set. The fiducial cross section for this process is measured in a data sample corresponding to an integrated luminosity of 20.3 fb(-1), collected by the ATLAS detector in 2012. Events are selected using the W boson decay to e nu or mu nu as well as requiring two isolated photons. The measured cross section is used to set limits on anomalous quartic gauge couplings in the high diphoton mass region.

Evolution of ATLAS conditions data and its management for LHC Run-2 / Boehler,Michael / 21ST INTERNATIONAL CONFERENCE ON COMPUTING IN HIGH ENERGY AND NUCLEAR PHYSICS (CHEP2015). - 2015.

Annotation:

The ATLAS detector at the LHC consists of several sub-detector systems. Both data taking and Monte Carlo (MC) simulation rely on an accurate description of the detector conditions from every subsystem, such as calibration constants, different scenarios of pile-up and noise conditions, size and position of the beam spot, etc. In order to guarantee database availability for critical online applications during data-taking, two database systems, one for online access and another one for all other database access, have been implemented. The long shutdown period has provided the opportunity to review and improve the Run-1 system: revise work flows, include new and innovative monitoring and maintenance tools and implement a new database instance for Run-2 conditions data. The detector conditions are organized by tag identification strings and managed independently by the different sub-detector experts. The individual tags are then collected and associated into a global conditions tag, assuring synchronization of various sub-detector improvements. Furthermore, a new concept was introduced to maintain conditions over all different data run periods into a single tag, by using Interval of Validity (IOV) dependent detector conditions for the MC database as well. This allows on the fly preservation of past conditions for data and MC and assures their sustainability with software evolution. This paper presents an overview of the commissioning of the new database instance, improved tools and work flows, and summarizes the actions taken during the Run-2 commissioning phase in the beginning of 2015.

Experimental parameters for a Cerium 144 based intense electron antineutrino generator experiment at very short baselines / Gaffiot,J / PHYSICAL REVIEW D. - 2015.

Annotation:

The standard three-neutrino oscillation paradigm, associated with small squared mass splittings Delta m(2) 0.1 eV(2), has been successfully built up over the last 15 years using solar, atmospheric, long baseline accelerator and reactor neutrino experiments. However, this well-established picture might suffer from anomalous results reported at very short baselines in some of these experiments. If not experimental artifacts, such results could possibly be interpreted as the existence of at least an additional fourth sterile neutrino species, mixing with the known active flavors with an associated mass splitting Delta m(new)(2) 0.01 eV(2) and being insensitive to standard weak interactions. Precision measurements at very short baselines (5-15 m) with intense MeV (nu) over bar (e) emitters can be used to probe these anomalies. In this article, the expected (nu) over bar (e) signal and backgrounds of a generic experiment which consists of deploying an intense beta(-) radioactive source inside or in the vicinity of a large liquid scintillator detector are studied. The technical challenges to perform such an experiment are identified, along with quantifying the possible source- and detector-induced systematics and their impact on the sensitivity to the observation of neutrino oscillations at short baselines.

Experimental test of the system of vertical and longitudinal lithium limiters on T-11M tokamak as a prototype of plasma facing components of a steady-state fusion neutron source / Belov,A.M. / Nuclear Fusion. - 2015.

Annotation:

A new functional model of the prototype of closed Li circuit for protection of the chamber wall was tested in T-11M tokamak by simultaneous use of the vertical Li limiter as an emitter of Li and a new longitudinal Li limiter as its collector. Such technological scheme can be suggested for the steady-state fusion neutron source on the tokamak basis. During plasma shots the cryogenic target of T-11M collected Li flow emitted by the vertical capillary Li limiter almost completely (up to 80%). These Li and hydrogen isotopes were captured and extracted outside the tokamak vacuum chamber without venting of the vessel which is a key requirement for the use of Li in the steady-state tokamak reactor. © 2015 IAEA, Vienna.

Fadin,V.V. Influence of cold working on the wear of AISI 1020 steel in dry sliding contact at high current density / Fadin,V.V., Aleutdinova,M.I. / Steel in Translation. - 2015.

Annotation:

The wear rate and surface electrical conductivity in the sliding electrocontact of 1020 steel and quenched steel are studied as a function of the current, at a contact current density exceeding 100 A/cmsup2/sup, without lubricant. The wear resistance is greater for steel with greater cold working. This may be attributed to the lower amplitude of the stress in low-cycle fatigue of the material adjacent to the contact spot of the stronger steel. The contact characteristics observed for the 1020 steel are somewhat higher than the known values for quenched steel. This may be attributed to the higher reserve of plasticity of the surface layer in 1020 steel than in quenched steel. Structural changes in the sliding surface are observed: specifically, the formation of a friction induced structure layer containing crystalline phases (FeO, α Fe, and γ Fe). An image of the worn surface shows indications of liquid phase. This phase is the result not of melting but of the appearance of highly excited atoms in a thin surface layer. © 2015, Allerton Press, Inc.

Fadin,V.V. Wear resistance of steels under conditions of sliding friction and high-density electric current passage / Fadin,V.V., Kulikova,O.A., Aleutdinova,M.I. / Inorganic Materials: Applied Research. - 2015.

Annotation:

Current dependences of the electrical conductivity and wear rate of a steel—steel 45 electrical contact under dry friction at a current density of over 100 A/cmsup2/sup are presented. It is found that an increase in the concentration of the alloying elements or the hardening phases in the original steel structure leads to a low strength of the surface layer, which manifests itself as a high wear rate of the contact and catastrophic wear at a low current density. © 2015, Pleiades Publishing, Ltd.

Fadin,V.V. About Wear and Average Surface Temperature of Copper or Steel Contacts at Sliding Current Collection / Fadin,VV, Rubtsov,VYe, Aleutdinova,MI / INTERNATIONAL CONFERENCE ON ADVANCED MATERIALS WITH HIERARCHICAL STRUCTURE FOR NEW TECHNOLOGIES AND RELIABLE STRUCTURES 2015.

Annotation:

Wear intensity and the average surface temperature of contact between copper and 1020 steel in dry sliding with a contact density higher 100 A/cm(2) are defined. It is shown that the temperature decreases linearly along the specimen with an increasing of distance from a contact surface. It is established that copper forms a friction zone with lower average contact surface temperature and with lower wear intensity in comparison with those of 1020 steel. It is caused by the lower local shear stability of copper comparing with that of 1020 steel. The explanation of this fact is offered on the basis of idea of low copper shear stability (i.e. copper high plasticity) that leads to easy relaxation of mechanical stresses in the field of stress concentrators. In this case, the surface layer is deformed locally at the low structural level and the low speed of structural defects formation is manifested. Rather high fatigue resistance of a surface layer takes place as a result. These factors and high heat conductivity of copper cause high shear stability of a surface layer at the macro-scale structural level that promotes weak heating and high wear resistance. Iron (unlike copper) has rather low heat conductivity and higher local shear stability. It leads to more difficult tension relaxation in a surface layer, as well as average temperature increasing and higher speed of deterioration.

Fadin,V.V. Structural Changes in the Surface Layer of Carbon Steels Under Friction and Current Loading in Air and in Liquid Media / Fadin,VV, Kolubaev,AV, Aleutdinova,MI / RUSSIAN PHYSICS JOURNAL. - 2015.

Annotation:

The current dependence of the electrical conductivity and wear intensity of a sliding electrical contact in air, glycerin, or electrolyte under electrolysis conditions at a contact current density of 100 A/Nm(2) is presented. The structural characteristics of the steel surface layer are shown to change due to the formation of the gamma-iron and ferric carbide phases. Low phase content is found to cause higher wear intensity of the sliding contact.

Fedorenko,D.N. Mobile rescue equipment for emergency response and recovery / Fedorenko,D.N., Kravchenko,P.D. / International Journal of Applied Engineering Research. - 2015.

Annotation:

Emergency response during rescue operations will be successful with the use of fast-reliable mobile equipment that provides the minimum time of the transactions. The proposed concept of mobile equipment contributes to this problem. The main elements of the basic requirements for the quality of its manufacture and use are represented. An example of a constructive scheme of fast assembled jib crane is shown. © Research India Publications.

Fesenko,V. The Increased Shape Memory Effect in Rolled Ti-48%Ni-2%Fe Single Crystals / Fesenko,V., Perlovich,Y., Isaenkova,M. / Materials Today: Proceedings. - 2015.

Annotation:

Shape memory effect (SME) for rolled single crystals from Ti-48%Ni-2%Fe alloy were measured by tensile deformation in the thermo-cryogenic set, adjusted to the standard tearing machine. The record SME - 100% shape recovery by assigning deformation degree of 15% - was attained for the single crystal, rolled in orientation 111<112>, annealed at 873 K and tested at the temperature of R→B19' phase transition. Tension of samples at ~ 160. K was conjugated with "superplastic" deformation up to deformation degrees ~50%. © 2015.

First constraints on the ultra-high energy neutrino flux from a prototype station of the Askaryan Radio Array / Allison,P. / Astroparticle Physics. - 2015.

Annotation:

Abstract The Askaryan Radio Array (ARA) is an ultra-high energy (>10sup17/sup eV) cosmic neutrino detector in phased construction near the south pole. ARA searches for radio Cherenkov emission from particle cascades induced by neutrino interactions in the ice using radio frequency antennas (∼150-800 MHz) deployed at a design depth of 200 m in the Antarctic ice. A prototype ARA Testbed station was deployed at ∼30 m depth in the 2010-2011 season and the first three full ARA stations were deployed in the 2011-2012 and 2012-2013 seasons. We present the first neutrino search with ARA using data taken in 2011 and 2012 with the ARA Testbed and the resulting constraints on the neutrino flux from 10sup17/sup-10sup21/sup eV. © 2015 Elsevier B.V.

First direct high-precision energy determination for the 8.4 and 20.7 keV nuclear transitions in sup169/supTm / Inoyatov,A.K. / European Physical Journal A. - 2015.

Annotation:

Energies of 8410.1 ± 0.4, 20743.9 ± 0.3, and 63121.6 ± 1.2 eV were determined for the 8.4 keV M1 + E2, 20.7 keV M1 + E2, and 63.1 keV E1 nuclear transitions in sup169/supTm (generated in the EC decay of sup169/supYb, respectively, by means of the internal conversion electron spectroscopy. The sup169/supYb sources used were prepared by vacuum evaporation deposition on polycrystalline carbon and platinum foils as well as by ion implantation at 30keV into a polycrystalline aluminum foil. The relevant conversion electron spectra were measured by a high-resolution combined electrostatic electron spectrometer at 7 eV instrumental resoluition. Values of 0.0326(14) and 0.0259(17) were derived from our experimental data for the E2 admixture parameter |δ (E2/M1)| for the 8.4 and 20.7 keV transitions, respectively. A possible effect of nuclear structure on multipolarity of the 20.7 keV transition was also investigated. © 2015, SIF, Springer-Verlag Berlin Heidelberg.

First Observation of CP Violation in B Ї 0 → DCP (∗) h0 Decays by a Combined Time-Dependent Analysis of BABAR and Belle Data / Abdesselam,A. / Physical Review Letters. - 2015.

Annotation:

We report a measurement of the time-dependent CP asymmetry of B¯0→DCP(∗)h0 decays, where the light neutral hadron h0 is a π0, η, or ω meson, and the neutral D meson is reconstructed in the CP eigenstates K+K-, KS0π0, or KS0ω. The measurement is performed combining the final data samples collected at the (4S) resonance by the BABAR and Belle experiments at the asymmetric-energy B factories PEP-II at SLAC and KEKB at KEK, respectively. The data samples contain (471±3)×106BB¯ pairs recorded by the BABAR detector and (772±11)×106BB¯ pairs recorded by the Belle detector. We measure the CP asymmetry parameters -ηfS=+0.66±0.10(stat)±0.06(syst) and C=-0.02±0.07(stat)±0.03(syst). These results correspond to the first observation of CP violation in B¯0→DCP(∗)h0 decays. The hypothesis of no mixing-induced CP violation is excluded in these decays at the level of 5.4 standard deviations. © 2015 American Physical Society. © 2015 American Physical Society.

First Observation of the Hadronic Transition Γ (4S) →ηhb (1P) and New Measurement of the hb (1P) and ηb (1S) Parameters / Tamponi,U. / Physical Review Letters. - 2015.

Annotation:

Using a sample of 771.6×106 ΓΓ(4S) decays collected by the Belle experiment at the KEKB e+e- collider, we observe, for the first time, the transition Γ(4S)→ηhb(1P) with the branching fraction B[Γ(4S)→ηhb(1P)]=(2.18±0.11±0.18)×10-3 and we measure the hb(1P) mass Mhb(1P)=(9899.3±0.4±1.0)MeV/c2, corresponding to the hyperfine (HF) splitting ΔMHF(1P)=(0.6±0.4±1.0)MeV/c2. Using the transition hb(1P)→γηb(1S), we measure the ηb(1S) mass Mηb(1S)=(9400.7±1.7±1.6)MeV/c2, corresponding to ΔMHF(1S)=(59.6±1.7±1.6)MeV/c2, the ηb(1S) width Γηb(1S)=(8-5+6±5)MeV/c2 and the branching fraction B[hb(1P)→γηb(1S)]=(56±8±4)%. © 2015 American Physical Society.

First results from the DarkSide-50 dark matter experiment at Laboratori Nazionali del Gran Sasso / Agnes,P. / Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 2015.

Annotation:

We report the first results of DarkSide-50, a direct search for dark matter operating in the underground Laboratori Nazionali del Gran Sasso (LNGS) and searching for the rare nuclear recoils possibly induced by weakly interacting massive particles (WIMPs). The dark matter detector is a Liquid Argon Time Projection Chamber with a (46.4±0.7)kg active mass, operated inside a 30 t organic liquid scintillator neutron veto, which is in turn installed at the center of a 1 kt water Cherenkov veto for the residual flux of cosmic rays. We report here the null results of a dark matter search for a (1422±67)kgd exposure with an atmospheric argon fill. This is the most sensitive dark matter search performed with an argon target, corresponding to a 90% CL upper limit on the WIMP-nucleon spin-independent cross section of 6.1×10-44cm2 for a WIMP mass of 100Gev/c2. © 2015 The Authors.

First Results on Observation of New Shape Isomers / Kamanin,D.V. / Physics Procedia. - 2015.

Annotation:

In our previous publications devoted to the collinear cluster tri-partition (CCT) of the low excited nuclei [1,2] we have discussed the role of scattering medium in the registration of the CCT products. This decay mode has been called by us "collinear cluster tri-partition" (CCT) in view of the observed features of the effect, that the decay partners fly apart almost collinearly and at least one of them has magic nucleon composition. Briefly, even if initially two CCT partners fly in the same direction perfectly collinearly they get some angular divergence after passing the scattering medium on the flight pass due to the multiple scattering. Thanks to such effect they can be registered independently in the "stop" mosaic detector. Actually even thin backing of the radioactive source provides the observable effect. © 2015 The Authors.

Force-field parameterization of the galactic cosmic ray spectrum: Validation for Forbush decreases / Usoskin,I.G. / Advances in Space Research. - 2015.

Annotation:

A useful parametrization of the energy spectrum of galactic cosmic rays (GCR) near Earth is offered by the so-called force-field model which describes the shape of the entire spectrum with a single parameter, the modulation potential. While the usefulness of the force-field approximation has been confirmed for regular periods of solar modulation, it was not tested explicitly for disturbed periods, when GCR are locally modulated by strong interplanetary transients. Here we use direct measurements of protons and α-particles performed by the PAMELA space-borne instrument during December 2006, including a major Forbush decrease, in order to directly test the validity of the force-field parameterization. We conclude that (1) The force-field parametrization works very well in describing the energy spectra of protons and α-particles directly measured by PAMELA outside the Earths atmosphere; (2) The energy spectrum of GCR can be well parameterized by the force-field model also during a strong Forbush decrease; (3) The estimate of the GCR modulation parameter, obtained using data from the world-wide neutron monitor network, is in good agreement with the spectra directly measured by PAMELA during the studied interval. This result is obtained on the basis of a single event analysis, more events need to be analyzed. © 2015 COSPAR.

Forecasting environmental health risks based on the kinetic theory of aging of living systems / Viktorov,A.A. / Advances in Gerontology. - 2015.

Annotation:

A method of iterative congruence for searching for the parameters of a kinetic mathematical model for aging of living systems using medical statistics data is developed. Its possibilities for describing risk functions of mortality and life expectancy for humans and animals depending on environmental factors are illustrated. The concept of forecasting environmental risks, i.e., risks to the population’s health from ecological factors, is formulated. © 2015, Pleiades Publishing, Ltd.

Formation of gradient structures during high-consolidation of powder materials / Yudin,A.V. / Physics Procedia. - 2015.

Annotation:

In this paper, the patterns forming a gradient structure with high-electro-consolidation (HEPC) carbonyl iron were identified. Map compactibility carbonyl iron powder was built. According to the table density plot the density of the samples on the parameters of sintering at constant pressure and discharge voltage. Experimental data on the density distribution across the sample were obtained. © 2015 Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license.

Formation of hydrogen isotopes in reactions of stopped pion absorption / Gurov,Y.B. / Bulletin of the Russian Academy of Sciences: Physics. - 2015.

Annotation:

Results are presented from analyzing the yields of protons (p), deuterons (d), and tritons (t) in pre-equilibrium stopped pion absorption reactions. Phenomenological formulas are proposed for describing the mass-number (A) dependences of these yields accurate to within 10–20% in the mass-number range of 6 < A < 209 (59 < A < 209 for t). The final results do not contradict the hypothesis that the predominant role in the formation of deuterons and tritons is played by pick-up on the surface of nuclei. © 2015, Allerton Press, Inc.

Formation of multilayer claddings using high-power fiber laser radiation / Bykovskiy,D.P. / Physics Procedia. - 2015.

Annotation:

Fabricated and investigated samples of multilayer cladding on the flat surface are obtained using a laser cladding technology. Iron-based powder was used in the study. Geometric parameters of track depending on the process parameters were determined. The effect of thermal fields on the quality of the coating was analyzed. Optimal strategy areas adjacent to tracks and each subsequent layer deposition have been identified. Microhardness of the resulting coatings was measured. Result of this work is a multi-layer coating in order to restore and improve the surfaces of parts, which exposed to wear. © 2015 The Authors.

Forward-backward multiplicity correlations in pp collisions at √s = 0.9, 2.76 and 7 TeV / TheALICEcollaboration / Journal of High Energy Physics. - 2015.

Annotation:

Abstract: The strength of forward-backward (FB) multiplicity correlations is measured by the ALICE detector in proton-proton (pp) collisions at s$$ s $$ = 0.9, 2.76 and 7 TeV. The measurement is performed in the central pseudorapidity region (|η| < 0.8) for the transverse momentum pinfT/inf> 0.3 GeV/c. Two separate pseudorapidity windows of width (δη) ranging from 0.2 to 0.8 are chosen symmetrically around η = 0. The multiplicity correlation strength (binfcorr/inf) is studied as a function of the pseudorapidity gap (ηinfgap/inf) between the two windows as well as the width of these windows. The correlation strength is found to decrease with increasing ηinfgap/inf and shows a non-linear increase with δη. A sizable increase of the correlation strength with the collision energy, which cannot be explained exclusively by the increase of the mean multiplicity inside the windows, is observed. The correlation coefficient is also measured for multiplicities in different configurations of two azimuthal sectors selected within the symmetric FB η-windows. Two different contributions, the short-range (SR) and the long-range (LR), are observed. The energy dependence of binfcorr/inf is found to be weak for the SR component while it is strong for the LR component. Moreover, the correlation coefficient is studied for particles belonging to various transverse momentum intervals chosen to have the same mean multiplicity. Both SR and LR contributions to binfcorr/inf are found to increase with pinfT/inf in this case. Results are compared to PYTHIA and PHOJET event generators and to a string-based phenomenological model. The observed dependencies of binfcorr/inf add new constraints on phenomenological models.[Figure not available: see fulltext.] © 2015, The Author(s).

Fre,P. Classification of Arnold-Beltrami flows and their hidden symmetries / Fre,P, Sorin,AS / PHYSICS OF PARTICLES AND NUCLEI. - 2015.

Annotation:

In the context of mathematical hydrodynamics, we consider the group theory structure which underlies the so named ABC flows introduced by Beltrami, Arnold and Childress. Main reference points are Arnold's theorem stating that, for flows taking place on compact three manifolds a"(3)(3), the only velocity fields able to produce chaotic streamlines are those satisfying Beltrami equation and the modern topological conception of contact structures, each of which admits a representative contact one-form also satisfying Beltrami equation. We advocate that Beltrami equation is nothing else but the eigenstate equation for the first order Laplace-Beltrami operator a similar to... (g) d, which can be solved by using time-honored harmonic analysis. Taking for a"(3)(3), a torus T (3) constructed as a"e(3)/I , where I is a crystallographic lattice, we present a general algorithm to construct solutions of the Beltrami equation which utilizes as main ingredient the orbits under the action of the point group B (A) of three-vectors in the momentum lattice *I . Inspired by the crystallographic construction of space groups, we introduce the new notion of a Universal Classifying Group which contains all space groups as proper subgroups. We show that the a similar to... (g) d eigenfunctions are naturally arranged into irreducible representations of and by means of a systematic use of the branching rules with respect to various possible subgroups we search and find Beltrami fields with non trivial hidden symmetries. In the case of the cubic lattice the point group is the proper octahedral group O-24 and the Universal Classifying Group is a finite group G(1536) of order |G(1536)| = 1536 which we study in full detail deriving all of its 37 irreducible representations and the associated character table. We show that the O-24 orbits in the cubic lattice are arranged into 48 equivalence classes, the parameters of the corresponding Beltrami vector fields filling all the 37 irreducible representations of G(1536). In this way we obtain an exhaustive classification of all generalized ABC-flows and of their hidden symmetries. We make several conceptual comments about the need of a field-theory yielding Beltrami equation as a field equation and/or an instanton equation and on the possible relation of Arnold-Beltrami flows with (supersymmetric) Chern-Simons gauge theories. We also suggest linear generalizations of Beltrami equation to higher odd-dimensions that are different from the non-linear one proposed by Arnold and possibly make contact with M-theory and the geometry of flux-compactifications.

Fré,P. 2-branes with Arnold-Beltrami fluxes from minimal D=7 supergravity / Fré,P., Sorin,A.S. / Fortschritte der Physik. - 2015.

Annotation:

We describe this paper as a Sentimental Journey from Hydrodynamics to Supergravity. Beltrami equation in three dimensions that plays a key role in the hydrodynamics of incompressible fluids has an unsuspected relation with minimal supergravity in seven dimensions. We show that just D=7 supergravity and no other theory with the same field content but different coefficients in the lagrangian, admits exact two-brane solutions where Arnold-Beltrami fluxes in the transverse directions have been switched on. The rich variety of discrete groups that classify the solutions of Beltrami equation, namely the eigenfunctions of the star, opend operator on a three-torus, are by this newly discovered token injected into the brane world. A new quite extensive playing ground opens up for supergravity and for its dual gauge theories in three dimensions, where all classical fields and all quantum composite operators will be assigned to irreducible representations of discrete crystallographic groups Γ. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Galakhov,D. Wall-crossing invariants: from quantum mechanics to knots / Galakhov,D., Mironov,A., Morozov,A. / Journal of Experimental and Theoretical Physics. - 2015.

Annotation:

We offer a pedestrian-level review of the wall-crossing invariants. The story begins from the scattering theory in quantum mechanics where the spectrum reshuffling can be related to permutations of S-matrices. In nontrivial situations, starting from spin chains and matrix models, the S-matrices are operatorvalued and their algebra is described in terms of R- and mixing (Racah) U-matrices. Then the Kontsevich-Soibelman (KS) invariants are nothing but the standard knot invariants made out of these data within the Reshetikhin-Turaev-Witten approach. The R and Racah matrices acquire a relatively universal form in the semiclassical limit, where the basic reshufflings with the change of moduli are those of the Stokes line. Natural from this standpoint are matrices provided by the modular transformations of conformal blocks (with the usual identification R = T and U = S), and in the simplest case of the first degenerate field (2, 1), when the conformal blocks satisfy a second-order Shrödinger-like equation, the invariants coincide with the Jones (N = 2) invariants of the associated knots. Another possibility to construct knot invariants is to realize the cluster coordinates associated with reshufflings of the Stokes lines immediately in terms of check-operators acting on solutions of the Knizhnik-Zamolodchikov equations. Then the R-matrices are realized as products of successive mutations in the cluster algebra and are manifestly described in terms of quantum dilogarithms, ultimately leading to the Hikami construction of knot invariants. © 2015, Pleiades Publishing, Inc.

Galiakhmetov,A.M. Wormholes without exotic matter in Einstein–Cartan theory / Galiakhmetov,A.M., Bronnikov,K.A. / Gravitation and Cosmology. - 2015.

Annotation:

We study the possible existence of static traversable wormholes without invoking exotic matter in the framework of the Einstein–Cartan theory. A family of exact static, spherically symmetric wormhole solutions with an arbitrary throat radius, with flat or AdS asymptotic behavior, has been obtained with sources in the form of two noninteracting scalar fields with nonzero potentials. Both scalar fields are canonical (that is, satisfy the weak energy condition), one is minimally and the other nonminimally coupled to gravity, and the latter is a source of torsion. © 2015, Pleiades Publishing, Ltd.

GAMMA-400 Space Gamma-telescope Mathematical Model with Engineering Elements Included / Topchiev,N.P. / Physics Procedia. - 2015.

Annotation:

Mathematical model creation is a necessary stage in scientific apparatus development. The mathematical model of gamma-ray telescope GAMMA-400 is used to emulate transport of various elementary particles through the apparatus. The new iteration of the model is based on precise technical drawings and includes all the elements of the real gamma-telescope. It is created in Geant4 environment. This model allows calculation of energy deposition not only in detectors, but in any part of the apparatus, including construction elements. Moreover, it supports creation of virtual sensitive volumes, allowing determination of the number and properties of particles passing through an arbitrary part of the construction. Software for automated creation of Geant4 model based on technical drawings in STEP 3D Model format was developed. This software is capable of making models of other apparatus based particularly on scintillation and strip detectors. © 2015 The Authors.

Gamma-telescopes Fermi/LAT and GAMMA-400 Trigger Systems Event Recognizing Methods Comparison / Arkhangelskaja,I.V. / Physics Procedia. - 2015.

Annotation:

Usually instruments for high-energy γ-quanta registration consists of converter (where γ-quanta produced pairs) and calorimeter for particles energy measurements surrounded by anticoincidence shield used to events identification (whether incident particle was charged or neutral). The influence of pair formation by γ-quanta in shield and the backsplash (moved in the opposite direction particles created due high energy γ-rays interact with calorimeter) should be taken into account. It leads to decrease both effective area and registration efficiency at E>10 GeV. In the presented article the event recognizing methods used in Fermi/LAT trigger system is considered in comparison with the ones applied in counting and triggers signals formation system of gamma-telescope GAMMA-400. The GAMMA-400 (Gamma Astronomical Multifunctional Modular Apparatus) will be the new high-apogee space γ-observatory. The GAMMA-400 consist of converter-tracker based on silicon-strip coordinate detectors interleaved with tungsten foils, imaging calorimeter make of 2 layers of double (x, y) silicon strip coordinate detectors interleaved with planes of CsI(Tl) crystals and the electromagnetic calorimeter CC2 consists only of CsI(Tl) crystals. Several plastics detections systems used as anticoincidence shield, for particles energy and moving direction estimations. The main differences of GAMMA-400 constructions from Fermi/LAT one are using the time-of-flight system with base of 50 cm and double layer structure of plastic detectors provides more effective particles direction definition and backsplash rejection. Also two calorimeters in GAMMA-400 composed the total absorbtion spectrometer with total thickness 25 X0 or 1.2 λ0 for vertical incident particles registration and 54 X0 or 2.5 λ0 for laterally incident ones (where λ0 is nuclear interaction length). It provides energy resolution 1-2% for 10 GeV-3.0×103 GeV events while the Fermi/LAT energy resolution does not reach such a value because of its calorimeter thickness is only 10 X0 and energy of registered particles is defined by shower profile analysis. Less than 3% photons will be wrongly recognized as electrons or protons in double-layer ACtop taking into account both temporal and amplitude trigger marker analysis methods during onboard processing in the counting and triggers signals formation system of GAMMA-400. The proton rejection factor will be 10-5. The Fermi/LAT based on a 4 × 4 array of identical towers each contains a tracker, calorimeter and data acquisition module. Each tracker consists of 18 x-y silicon-strip layers. The calorimeter in each tower made of eight layers in a hodoscopic arrangement for measure the three-dimensional profiles of showers permits corrections for energy leakage and enhances the capability to discriminate hadronic cosmic rays. The each layer consists of 12 CsI(Tl) based bars. The segmented anticoincidence shield covers the array of towers. Unfortunately, several types of biases lead to systematic effects caused high values of relative systematic uncertainties of the exposure, the number of signal events, the induced fractional signal and so on. For example non confirmed announcement of 133 GeV line detection and lost sources in different Fermi catalogues (1FGL, 2FGL, 3FGL) - just well seen in 2FGL Cygnus X-3 (J2032.1+4049) does not appear in 3FGL. It allows to conclude sufficient biases in LAT characteristics obtained methods and event recognized algorithms. Now Fermi/LAT operates during 7 years but effective caveats methods continuously to be proposed. Respectively, continuation of measurements with use of other telescopes is necessary, and realization of GAMMA-400 will allow improving the results. © 2015 The Authors.

Gani,V.A. Kink excitation spectra in the (1+1)-dimensional φ sup8/sup model / Gani,V.A., Lensky,V., Lizunova,M.A. / Journal of High Energy Physics. - 2015.

Annotation:

Abstract: We study excitation spectra of BPS-saturated topological solutions — the kinks — of the φsup8/sup scalar field model in (1 + 1) dimensions, for three different choices of the model parameters. We demonstrate that some of these kinks have a vibrational mode, apart from the trivial zero (translational) excitation. One of the considered kinks is shown to have three vibrational modes. We perform a numerical calculation of the kink-kink scattering in one of the considered variants of the φsup8/sup model, and find the critical collision velocity vinfcr/inf that separates the different collision regimes: inelastic bounce of the kinks at vinfin/inf ≥ vinfcr/inf, and capture at vinfin/inf< vinfcr/inf. We also observe escape windows at some values of vinfin/inf< vinfcr/inf where the kinks escape to infinity after bouncing off each other two or more times. We analyse the features of these windows and discuss their relation to the resonant energy exchange between the translational and the vibrational excitations of the colliding kinks. © 2015, The Author(s).

Gani,V.A. Two-dimensional Manifold with Point-like Defects / Gani,V.A., Dmitriev,A.E., Rubin,S.G. / Physics Procedia. - 2015.

Annotation:

We study a class of two-dimensional compact extra spaces isomorphic to the sphere S 2 in the framework of multidimensional gravitation. We show that there exists a family of stationary metrics that depend on the initial (boundary) conditions. All these geometries have a singular point. We also discuss the possibility for these deformed extra spaces to be considered as dark matter candidates. © 2015 The Authors.

Gani,V.A. Deformed compact extra space as dark matter candidate / Gani,VakhidA, Dmitriev,AlexanderE, Rubin,SergeyG / INTERNATIONAL JOURNAL OF MODERN PHYSICS D. - 2015.

Annotation:

We elaborate the possibility for a deformed extra space to be considered as the dark matter candidate. To perform calculations, a class of two-dimensional extra metrics was considered in the framework of the multidimensional gravity. It was shown that there exists a family of stationary metrics of the extra space possessing point-like defect. Estimation of cross-section of scattering of a particle of the ordinary matter on a spatial domain with deformed extra space is in agreement with the observational constraints.

Gas porosity evolution and ion-implanted helium behavior in reactor ferritic/martensitic and austenitic steels / Ageev,V.S. / Journal of Nuclear Materials. - 2015.

Annotation:

The peculiarities of gas porosity formation and helium retention and release in reactor ferritic/martensitic EP-450 and EP-450-ODS and austenitic ChS-68 steels are investigated by transmission electron microscopy and helium thermal desorption spectrometry (HTDS). The samples were irradiated by 40 keV He+ ions up to a fluence of 5 · 1020 m-2 at 293 and 923 K. An nonuniform distribution of helium bubbles and high-level gas swelling in ferritic/martensitic steels were found at high-temperature helium implantation. The same irradiation conditions result in formation of uniformly distributed helium bubbles and low-level swelling in ChS-68 steel. Temperature range of helium release from EP-450-ODS steel was considerably wider in comparison to HTDS-spectra of the EP-450 steel. A considerable quantity of helium is released from ODS steel in the high-temperature range after the main peak of the HTDS-spectrum.

Godunov,S.I. Double Higgs boson production in the models with isotriplets / Godunov,S.I., Vysotsky,M.I., Zhemchugov,E.V. / Physics of Atomic Nuclei. - 2015.

Annotation:

The enhancement of double Higgs boson production in the extensions of the Standard Model with extra isotriplets is studied. It is found that in see-saw type II model decays of new heavy Higgs can contribute to the double Higgs production cross section as much as Standard Model channels. In Georgi–Machacek model the cross section can be much larger since the custodial symmetry is preserved and the strongest limitation on triplet parameters is removed. © 2015, Pleiades Publishing, Ltd.

Godunov,S.I. Double Higgs production at LHC, see-saw type-II and Georgi-Machacek model / Godunov,S.I., Vysotsky,M.I., Zhemchugov,E.V. / Journal of Experimental and Theoretical Physics. - 2015.

Annotation:

The double Higgs production in the models with isospin-triplet scalars is studied. It is shown that in the see-saw type-II model, the mode with an intermediate heavy scalar, pp → H + X → 2h + X, may have the cross section that is comparable with that in the Standard Model. In the Georgi-Machacek model, this cross section could be much larger than in the Standard Model because the vacuum expectation value of the triplet can be large. © 2015, Pleiades Publishing, Inc.

Gray,D. Study of Rare Muon Decay: μ+ → e+ e - E + ve v-μ with Polarized Muons / Gray,D., Reid,T., Belyaev,N. / Physics Procedia. - 2015.

Annotation:

We studied the rare muon decay process μ+ → e+ e - e + ve v-μ. This Standard Model process is the background with respect to the signal process μ+ → e+ e - e + which is predicted by many extensions of the SM. We show that the process μ+ → e+ e - e + ve v-μ could be suppressed by cuts on the total energy of charged leptons in the kinematic region where the signal of new physics such as is expected to appear. Also, we demonstrated that angular distributions of decay products in the process μ+ → e+ e - e + ve v-μ are sensitive to the muon polarization and could be used to distinguish the signal of new physics μ+ → e+ e - e + from the background process μ+ → e+ e - e + ve v-μ. © 2015 The Authors.

Grobov,A.V. Large-scale regions of antimatter / Grobov,A.V., Rubin,S.G. / Physics of Atomic Nuclei. - 2015.

Annotation:

Amodified mechanism of the formation of large-scale antimatter regions is proposed. Antimatter appears owing to fluctuations of a complex scalar field that carries a baryon charge in the inflation era. © 2015, Pleiades Publishing, Ltd.

Grobov,A.V. Formation and search of large scale antimatter regions / Grobov,AV, Rubin,SG / INTERNATIONAL JOURNAL OF MODERN PHYSICS D. - 2015.

Annotation:

In this paper, we discuss a generation of large antimatter regions with sizes exceeding the critical surviving size. In the modern epoch, domains with high antimatter density evolve to single galaxies with a peculiar content of antihelium and antideuterium.

Grushin,A.S. On the structure of quasi-stationary laser ablation fronts in strongly radiating plasmas / Grushin,A.S., Basko,M.M., Novikov,V.G. / Physics of Plasmas. - 2015.

Annotation:

The effect of strong thermal radiation on the structure of quasi-stationary laser ablation fronts is investigated under the assumption that all the laser flux is absorbed at the critical surface. Special attention is paid to adequate formulation of the boundary-value problem for a steady-state planar ablation flow. The dependence of the laser-to-x-ray conversion efficiency φ r on the laser intensity IinfL/inf and wavelength λinfL/inf is analyzed within the non-equilibrium diffusion approximation for radiation transfer. The scaling of the main ablation parameters with IinfL/inf and λinfL/inf in the strongly radiative regime 1 - φ r 蠐 1 is derived. It is demonstrated that strongly radiating ablation fronts develop a characteristic extended cushion of "radiation-soaked" plasma between the condensed ablated material and the critical surface, which can efficiently suppress perturbations from the instabilities at the critical surface. © 2015 AIP Publishing LLC.

Hardware and software for ground tests of onboard charged particle spectrometers / Grishin,S.A. / Physics of Atomic Nuclei. - 2015.

Annotation:

The article presents a hardware and software complex for ground tests of onboard charged particle spectrometers that are designed at the National Research Nuclear University MEPhI for monitoring of nuclear-physical factors of space weather and can be installed in a wide class of satellites. The structural scheme and operating principles of component parts are discussed. The main algorithm and software features are presented. The technique of ground spectrometer tests and calibrations in various measurement modes at atmospheric cosmic particle flows, both in autonomous laboratories and in interface tests as part of a satellite, is also described. © 2015, Pleiades Publishing, Ltd.

Heat transfer during transition to nucleate boiling / Balakin,B.V. / International Journal of Heat and Mass Transfer. - 2015.

Annotation:

A wide variety of empirical studies that consider transition to nucleate boiling regime has been published so far. Most of them tend to quantify the process-specific heat transfer by means of statistical approximation of the experimental data. The derived relations are therefore valid in a limited range of heat flux and pressure variation. The present work describes a general way to estimate heat transfer coefficient upon the transition to nucleate boiling regime. An expression for the heat transfer coefficient is theoretically derived when the effects of the heating surface roughness are taken into account. This expression is validated against series of experiments on saturated water and liquid nitrogen at the atmospheric pressure. Our theory agrees well with experimental results. © 2015 Elsevier Ltd.

Heat transfer from Ni-W tapes in liquid nitrogen at different orientations in the field of gravity / Balakin,B.V. / Cryogenics. - 2015.

Annotation:

Ni-W tapes of the micrometric thickness are considered as the basis for the cost-effective manufacturing of coated conductors - the 2nd generation of high-temperature superconductor (HTS). Many HTS applications involve widely-available and inexpensive liquid nitrogen. The transition from superconducting to normal state may however occurs due to unexpected temperature fluctuations. In this case Ni-W tape is significantly heated by electrical current propagating through it. The amount of heat transferred from the tape to coolant is defined by heat transfer from the surface of tape to liquid nitrogen. The heat transfer, in turn, is strongly dependent on the tape orientation in the field of gravity. The present paper reports the experimental results on the heat transfer from Ni-W tape to a pool of liquid nitrogen. The heat transfer coefficients are quantified for three subsequent heat transfer regimes: natural convection of liquid nitrogen, nucleate boiling regime and film boiling. The dependence of heat transfer coefficient on inclination angle of the tape from vertical are experimentally clarified for each regime. The expression for the heat transfer coefficient at different inclination angles is derived for the case of nucleate boiling.

High magnetic field facility for cyclotron resonance investigation in semiconductors / Filippov,A.V. / IEEE Transactions on Plasma Science. - 2015.

Annotation:

In this paper, a compact high magnetic field facility for cyclotron resonance (CR) investigation in the mid-infrared range is presented. A technology of multiturn coils winding with microcomposite Cu-Nb wire was developed in the Sarov Physics and Technology Institute Norwegian University of Science and Technology Moscow Engineering Physics Institute for the fabrication of compact nondestructive solenoids up to 50 T. An optical scheme and details of experimental techniques of CR measurements are discussed. Two peaks of magnetic absorption at 28 THz were observed in a narrow-gap HgTe/Hg1-xCdxTe heterostructures with quantum wells at 80 K.

High-energy positrons and gamma radiation from decaying constituents of a two-component dark atom model / Kouvaris,C / INTERNATIONAL JOURNAL OF MODERN PHYSICS D. - 2015.

Annotation:

We study a two-component dark matter candidate inspired by the minimal walking technicolor (WTC) model. Dark matter consists of a dominant strongly interactive massive particle (SIMP)-like dark atom component made of bound states between primordial helium nuclei and a doubly charged technilepton and a small WIMP-like component made of another dark atom bound state between a doubly charged technibaryon and a technilepton. This scenario is consistent with direct search experimental findings because the dominant SIMP component interacts too strongly to reach the depths of current detectors with sufficient energy to recoil and the WIMP-like component is too small to cause significant amount of events. In this context, a metastable technibaryon that decays to e(+) e(+), mu(+) mu(+) and tau(+) tau(+) can, in principle, explain the observed positron excess by AMS-02 and PAMELA, while being consistent with the photon flux observed by FERMI/LAT. We scan the parameters of the model and we find the best possible fit to the latest experimental data. We find that there is a small range of parameter space that this scenario can be realized under certain conditions regarding the cosmic ray propagation and the final state radiation (FSR). This range of parameters fall inside the region where the current run of large hadron collider (LHC) can probe, and therefore it will soon be possible to either verify or exclude conclusively this model of dark matter.

High-Power Compact P-Band UHF Oscillator Based on Hollow Cathode Discharge / L'vov,IgorL / IEEE TRANSACTIONS ON PLASMA SCIENCE. - 2015.

Annotation:

This paper describes a novel high-power ultra high frequency oscillator based on hollow cathode gas discharge. The oscillator generates the pulses with a carrier frequency of 380 MHz, power of 390 kW, and pulse duration of 450 ns. The oscillator has been tested in a pulsed-periodical regime with a pulse repetition rate of 2.5 kHz. The lifetime of the oscillator is 107 pulses. The oscillator has been tested for operation into radiating three-element array of dipole antennas. These tests showed the oscillator and antenna array compliance.

Highly excited states of sup6/supHe / Gurov,Y.B. / Bulletin of the Russian Academy of Sciences: Physics. - 2015.

Annotation:

Highly excited states of sup6/supHe are sought in the reactions involved in the absorption of stopped pions by sup10,11/supB nuclei. Several levels in sup6/supHe are observed for the first time. A state with Einfx/inf ≈ 9.3(2) MeV and Γ ≈ 1.0(4) MeV is seen to form in two reactions: sup10/supB(πsup−/sup, pt)X and sup11/supB(πsup−/sup, dt)X. Two states are seen to form in the sup10/supB(πsup−/sup, pt)X reaction channel at energies above the threshold of sup6/supHe decay into two tritons (Einfx/inf ≥ 12.3 MeV): one state with Einfx/inf = 22(1) MeV, Γ = 2.7(1.4) MeV and the other with Einfx/inf = 27.0(8) MeV, Γ = 2.5(1.1) MeV. © 2015, Allerton Press, Inc.

Hybrid fusion–fission reactor with a thorium blanket: Its potential in the fuel cycle of nuclear reactors / Shmelev,A.N. / Physics of Atomic Nuclei. - 2015.

Annotation:

Discussions are currently going on as to whether it is suitable to employ thorium in the nuclear fuel cycle. This work demonstrates that the 231Pa–232U–233U–Th composition to be produced in the thorium blanket of a hybrid thermonuclear reactor (HTR) as a fuel for light-water reactors opens up the possibility of achieving high, up to 30% of heavy metals (HM), or even ultrahigh fuel burnup. This is because the above fuel composition is able to stabilize its neutron-multiplying properties in the process of high fuel burnup. In addition, it allows the nuclear fuel cycle (NFC) to be better protected against unauthorized proliferation of fissile materials owing to an unprecedentedly large fraction of 232U (several percent!) in the uranium bred from the Th blanket, which will substantially hamper the use of fissile materials in a closed NFC for purposes other than power production. © 2015, Pleiades Publishing, Ltd.

Hydrodynamic test bench / Bashurin,V.P. / Technical Physics. - 2015.

Annotation:

Methods of laboratory modeling of 2D water flows in a rectangular channel are developed. The flow is produced in a vertical tube of a rectangular cross section when water flows through the hole in the bottom of the tube. In the setup, a short-term (up to ∼15 s) laminar water flow with a velocity up to about 18 cm/s is produced. The methods for recording the flow velocity and the type of the flow past models of various shapes are developed © 2015, Pleiades Publishing, Ltd.

Hydrogen retention by vanadium-titanium alloys / Zaw,A.K. / Inorganic Materials: Applied Research. - 2015.

Annotation:

Hydrogen retention in vanadium and its binary alloys with titanium are investigated by means of hydrogen thermal desorption spectrometry. The samples are saturated with hydrogen for 2000 h at a temperature of 620 K in an autoclave, where hydrogen is fed at a pressure of 16.8 MPa. It is shown that in V-Ti alloys there are two main types of traps for hydrogen and from which the hydrogen release occurs in the temperature range of 780–790 (peak I) and 870–880 K (peak II) The position of peak I on the temperature scale does not depend on the alloy composition, and the intensity and position of peak II on the temperature scale are determined by the alloy composition. Titanium non-monotonically affects the amount of hydrogen retained: an addition of 0.5% Ti decreases, 1 and 5% Ti increases, and 10% Ti again decreases the amount of hydrogen in the alloy. A physical explanation of the appearance of two peaks of hydrogen thermal desorption and nonmonotonic influence of titanium on the amount of hydrogen in vanadium is proposed. © 2015, Pleiades Publishing, Ltd.

I&C system for critical facility upgrading / Jitarev,V.E./ 9th International Topical Meeting on Nuclear Plant Instrumentation, Control, and Human-Machine Interface Technologies, NPIC and HMIT 2015. - 2015.

Annotation:

Currently, the equipment of control and protection systems, as well as systems for the automation of physical experiments for a significant number of critical nuclear facilities operated in Russia, becomes obsolete and requires modernization or replacement with modern I&C on the basis of programmable controllers. At the MEPhl Department of Automatics, a hardware & software complex "PARUS" was developed, which may become the basis for projects of modernization of automated monitoring and control systems for critical facilities. The paper discusses the results of the development and use of a multichannel system for the RBMK critical facility at the NRC "Kurchatov Institute" that performs the functions of control and protection, automation of physical measurements of the neutron field and reactivity, and control of process parameters of the facility.

Identification and energy calibration of hadronically decaying tau leptons with the ATLAS experiment in pp collisions at root s=8 TeV / Aad,G / EUROPEAN PHYSICAL JOURNAL C. - 2015.

Annotation:

This paper describes the trigger and offline reconstruction, identification and energy calibration algorithms for hadronic decays of tau leptons employed for the data collected from pp collisions in 2012 with the ATLAS detector at the LHC center-of-mass energy root s = 8 TeV. The performance of these algorithms is measured in most cases with Z decays to tau leptons using the full 2012 dataset, corresponding to an integrated luminosity of 20.3 fb(-1). An uncertainty on the offline reconstructed tau energy scale of 2-4%, depending on transverse energy and pseudorapidity, is achieved using two independent methods. The offline tau identification efficiency is measured with a precision of 2.5% for hadronically decaying tau leptons with one associated track, and of 4% for the case of three associated tracks, inclusive in pseudorapidity and for a visible transverse energy greater than 20 GeV. For hadronic tau lepton decays selected by offline algorithms, the tau trigger identification efficiency is measured with a precision of 2-8%, depending on the transverse energy. The performance of the tau algorithms, both offline and at the trigger level, is found to be stable with respect to the number of concurrent proton-proton interactions and has supported a variety of physics results using hadronically decaying tau leptons at ATLAS.

Identification of Solar Coronal Mass Ejections in Cosmic Ray Flux Using Flicker Noise Spectroscopy / Borog,V.V. / Physics Procedia. - 2015.

Annotation:

In this article, we examine the possibility of applying the method of flicker noise spectroscopy to identification of anomalies in flux of cosmic rays (CR). Typically, such anomalies appears after intense solar outbursts, when the Sun emits into space giant blobs of plasma also called coronal mass ejection (CME). Identification of such anomalies in the CR flux allows us to detect CME, approaching to Earth. CMEs, powerful enough, can cause significant damage to electrical appliances. The present paper describes basic concepts of the flicker noise spectroscopy and principles of cosmic rays data processing algorithms. © 2015 The Authors.

Identification reliability for hydrogen isotopes detected in cosmic ray fluxes / Voronov,S.A. / Instruments and Experimental Techniques. - 2015.

Annotation:

A technique for identifying hydrogen isotopes based on experimental data obtained in the PAMELA satellite-borne experiment is analyzed. Discrimination of cosmic-ray deuteron fluxes from the background of proton fluxes with a significantly higher intensity using information from the magnetic spectrometer and the time-of-flight system is discussed. Selection of smooth functions for fitting experimentally measured distributions of the inverse particle velocity is considered. Criteria for verifying the correctness of detected particle counting are developed. © 2015, Pleiades Publishing, Inc.

Inclusive photon production at forward rapidities in proton–proton collisions at √s = 0.9, 2.76 and 7 TeV / ALICECollaboration / European Physical Journal C. - 2015.

Annotation:

The multiplicity and pseudorapidity distributions of inclusive photons have been measured at forward rapidities (2.3 < η < 3.9) in proton–proton collisions at three center-of-mass energies, √s = 0.9, 2.76 and 7 TeV using the ALICE detector. It is observed that the increase in the average photon multiplicity as a function of beam energy is compatible with both a logarithmic and a power-law dependence. The relative increase in average photon multiplicity produced in inelastic pp collisions at 2.76 and 7 TeV center-of-mass energies with respect to 0.9 TeV are 37.2± 0.3% (stat) ± 8.8% (sys) and 61.2 ± 0.3 % (stat) ± 7.6% (sys), respectively. The photon multiplicity distributions for all center-of-mass energies are well described by negative binomial distributions. The multiplicity distributions are also presented in terms of KNO variables. The results are compared to model predictions, which are found in general to underestimate the data at large photon multiplicities, in particular at the highest center-of-mass energy. Limiting fragmentation behavior of photons has been explored with the data, but is not observed in the measured pseudorapidity range. © 2015, CERN for the benefit of the ALICE collaboration.

Increasing of compatibility of metallic nuclear fuel with various construction materials / Nikitin,S.N. / Tsvetnye Metally. - 2015.

Annotation:

Nowadays, one of the most promising types of nuclear fuel for fast reactors is metallic fuel, based on Uzr, UPuZr and UMo alloys, having such advantages as high thermal conductivity, high density and excellent neutron- physical properties. Ferritic-martensitic steels, such as HT-9 and 9Cr, are offered as claddings with such fuel. These steels are exposed to little swelling during irradiation. Their advantages are good mechanical properties at high temperatures and resistance to metal coolants. During the exploitation, metal fuel comes into tight contact with metal sheath (because of swelling), which promotes the fuel-diffusion interaction at high temperature of the shell to form a liquid phase and fuel rod failure. Alloying of ferritic steels by barrier layer forming elements (Al, Si) is the promising way to improve the compatibility of metallic fuel with ferritic steels. This paper studies the diffusion interaction between UZr and UMo alloys with iron alloys. These results show that ferritic chromium steels have higher compatibility with metallic nuclear fuel, based on uranium-zirconium alloy, compared with austenitic chromium-nickel steel. Introduction of aluminum into Fe (13% (wt.) of Cr) leads to decrease in the rate of interaction of UZr core with the shell by more than 4 times. It was found that iron alloying with aluminum leads to a sharp reduction of interaction speed by forming a protective zirconium-enriched layer, which suppresses the formation of liquid phase to the temperature of 800 °C. In addition, there is shown the possibility of obtaining of in-situ protective coatings on ferritic chromium steel, which was alloyed by aluminum, using nitriding method.

Increasing Strength and Operational Reliability of Fixed Joints of Tubes by MMA Welding / Il'yaschenko,DP / VI INTERNATIONAL SCIENTIFIC PRACTICAL CONFERENCE ON INNOVATIVE TECHNOLOGIES AND ECONOMICS IN ENGINEERING. - 2015.

Annotation:

This paper presents peculiar properties of structure formation, phase and chemical composition while welding of low-alloy steel 09MnSi2-1 depending on the dynamic characteristics of power sources of different types. Proper selection of power sources enables to decrease burning of alloy elements in metal of weld (Mn by 14% and Si by 17% of the weight ratio), to obtain more homogenous structure of deposited metal, to reduce length of heat-affected zone by 50% and to improve impact strength by 4-9%.

Inelastic scattering and clusters transfer in sup3,4/supHe + sup9/supBe reactions / Denikin,A.S. / Physics of Particles and Nuclei Letters. - 2015.

Annotation:

A study of inelastic scattering and multi-particle transfer reactions was performed by alpha and sup3/supHe beams on a sup9/supBe target at energy about 50 MeV. Angular distributions of the differential cross sections for the sup9/supBe(α,α′)sup9/supBe*, sup9/supBe(α,sup3/supHe)sup10/supBe, sup9/supBe(α,t)sup10/supB, sup9/supBe(sup3/supHe,sup6/supLi)sup6/supLi and sup9/supBe(sup3/supHe,sup6/supBe)sup6/supHe reactions were measured. Experimental angular distributions of the differential cross sections for the ground state and a few low-lying states were analyzed in the framework of the optical model, coupled channels and distorted-wave Born approximation. The information on the cluster structure of the reaction products are obtained. An analysis of the obtained spectroscopic factors was performed. © 2015, Pleiades Publishing, Ltd.

Influence of additions of nanoparticles TaC on a microstructure laser cladding / Tret'Yakov,E.V. / Journal of Physics: Conference Series. - 2015.

Annotation:

The features of a laser cladding of nickel-based powders with TaC nanopowder additives have been experimentally investigated. The minimum depth of pro-melting of a basis, microhardness distribution over the cross section of the substrate, and the saturation of the metal of the cladding with basis components has been determined in the experiments. © Published under licence by IOP Publishing Ltd.

Influence of high-temperature oxidation on structural and textural peculiarities of cladding pipes, made of Zr - 1% Nb alloy / Perlovich,Yu.A. / Tsvetnye Metally. - 2015.

Annotation:

X-ray diffractometric methods investigated the cladding pipes, made of Zr - 1%Nb alloy, manufactured from spongy and electrolytic zirconium and oxidized at high temperature (1100 °C). The layer-by-layer study of oxide phase composition was investigated together with structural and textural peculiarities of pipe layers, adjacent to oxidation zone. According to the enterprise-adopted criteria, preliminary recrystallization of both pipes is complete. The whole deformed matrix is replaced by newly formed recrystallized grains. However, the size of these grains can be significantly varied, depending on the density of recrystallization nucleus distribution and their growth rate, certainly differing in alloys, based on spongy and electrolytic zirconium. A number of X-ray data testifies, that recrystallization of investigated pipes proceeds in different manners, with formation of new different size grains. The defined difference in recrystallized grain sizes is critical for the pipe completeness with high-temperature oxidation. Electrolytic zirconium pipe destruction is connected with prevalence of tetragonal phase in its oxide layer. This is explained by intense diffusion of oxygen into pipe wall, subjected to recrystallization with final thermal treatment with formation of more fine-grain structure, than spongy zirconium pipe.

Influence of operation factors on brittle fracture initiation and critical local normal stress in SE(B) type specimens of VVER reactor pressure vessel steels / Erak,A.D. / Journal of Nuclear Materials. - 2015.

Annotation:

A complex of mechanical tests and fractographic studies of VVER-1000 RPV SE(B) type surveillance specimens was carried out: the brittle fracture origins were revealed (non-metallic inclusions and structural boundaries) and the correlation between fracture toughness parameters (CTOD) and fracture surface parameters (CID) was established. A computational and experimental method of the critical local normal stress determination for different origin types was developed. The values of the critical local normal stress for the structural boundary origin type both for base and weld metal after thermal exposure and neutron irradiation are lower than that for initial state due to the lower cohesive strength of grain boundaries as a result of phosphorus segregation. © 2015 Elsevier B.V.

Influence of pressure in flash sintering technique / Olevsky,E.A. / Physics Procedia. - 2015.

Annotation:

An innovative pressure-assisted flash-sintering technique has been developed to investigate the effect of pressure applied on microstructure and the sintering behavior of titanium dioxide. There are numerous applications for titanium dioxide in ceramics including microeletronics, glass ceramics, refractive materials, structural ceramics and titanium-containing ceramic materials and chemical intermediates. The traditional sintering of titanium dioxide usually requires several hours at over 1200°C. The conducted research indicates that titanium dioxide can be sintered to full density in only a few seconds at 800-1000°C, when subjected to a DC electrical field at a certain temperature moment. © 2015 Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license.

Influence of the ionization-energy losses of high-energy bismuth ions on the development of helium blisters in silicon / Reutov,V.F. / Semiconductors. - 2015.

Annotation:

Understanding the behavior of helium in solids under conditions of intense ionizing radiation is of particular interest in solving many problems of nuclear, fusion, and space materials science and also in microelectronics. The observed effect of suppressing the formation of helium blisters on the surface of helium ion-doped silicon as a result of irradiation with high-energy bismuth ions is reported in this publication. It is suggested that a possible decrease in the concentration of helium atoms in silicon is due to their radiationinduced desorption from the area of doping in terms of the high-impact ionization of bismuth ions. © 2015, Pleiades Publishing, Ltd.

Interaction of self-point defects with low-angle tilt boundaries in BCC iron and vanadium crystals / Sivak,A.B. / Problems of Atomic Science and Technology, Series Thermonuclear Fusion. - 2015.

Annotation:

Stress fields of dislocation agglomerations (boundaries of different types) significantly affect the formation and kinetics of self-point defects (SPDs: vacancies and self-interstitial atoms) determining additional features of formation and decomposition of SPD solid solu-tions. Therefore it is important to study the influence of the dislocation agglomerations (boundaries) stress fields on the SPD formation and migration energies in crystals with different elastic anisotropy. Spatial dependence of the interaction energy of SPDs with low-angle tilt boundaries (infinite dislocation walls consisting of edge dislocations in slip systems 111110 and 111112) in bcc iron and vanadium crystals has been calculated within the anisotropic theory of elasticity. Distances to the boundaries, at which this interaction appreciably affects the behaviour of SPDs against the temperature and the boundary misorientation angle have been determined. At spa-tially homogeneous generation of SPDs throughout the whole crystal volume, their fluxes from the left and the right onto a low-angle tilt boundary can differ.

Interrelation between energy and time distributions of high- energy electrons during the observation of the particle bursts in the near-Earth space / Aleksandrin,S.Yu. / Journal of Physics: Conference Series. - 2015.

Annotation:

Many satellite experiments showed interrelation between changes of particle fluxes in the near-Earth space and various magnetospheric and geophysical phenomena. In this report we focus on temporal and energy characteristics of bursts of high-energy electrons in the inner zone of the Earth's magnetosphere (L<2). In order to study the variations of electron characteristics during the observation of the bursts, caused by local disturbances of the radiation belt (e.g. lightning or seismic events), numerical modelling the propagation of particle cloud formed by electrons, precipitated from radiation belt, has been carried out. It was shown a relationship between energy distribution and temporal profile of electrons of burst in case of their local precipitation. The results of simulation are analyzed and compared with the data obtained in ARINA and VSPLESK satellite experiments. © Published under licence by IOP Publishing Ltd.

Investigating highly excited states of sup9/supLi in the pion absorption reaction / Gurov,Y.B. / Bulletin of the Russian Academy of Sciences: Physics. - 2015.

Annotation:

Highly excited states in sup9/supLi are sought in missing mass spectra measured in the stopped pion absorption reaction sup11/supB(πsup−/sup, dt)X. Observed for the first time in the two-particle reaction πsup−/sup + sup11/supB → d + sup9/supLi* was a highly excited sup9/supLi state with Einfx/inf = 12.0 ± 0.5 MeV that decayed with the emission of a triton. © 2015, Allerton Press, Inc.

Investigating the albedo muon flux at the NEVOD-DECOR experimental complex / Kruglikova,V.S. / Bulletin of the Russian Academy of Sciences: Physics. - 2015.

Annotation:

New results from investigating the flux of atmospheric muons scattered from the ground to the upper hemisphere, obtained with the NEVOD-DECOR experimental complex from December 2011 to March 2013, are presented. © 2015, Allerton Press, Inc.

Investigating the energy characteristics of muon bundles in inclined EAS / Mannocchi,G. / Bulletin of the Russian Academy of Sciences: Physics. - 2015.

Annotation:

The first results from studying the energy deposits of inclined muon bundles in a Cherenkov water detector on the Earth’s surface are presented. The general response of the NEVOD Cherenkov calorimeter’s PMT is used as a measure of the energy deposited (proportional to the muon energy losses in the detector’s matter), while the local muon density at the point of observation is estimated using data from the DECOR coordinate-tracking detector. It is found that the energy deposit normalized to the muon density depends largely on the zenith angle. A comparison of the experimental results and those from EAS muon component simulations using the CORSIKA package shows that the average energy of muons detected in the bundles grows rapidly as the zenith angle increases, reaching ∼500 GeV near the horizon. © 2015, Allerton Press, Inc.

Investigating the relationship between the NEVOD Cherenkov water detector’s response and water transparency / Kindin,V.V. / Bulletin of the Russian Academy of Sciences: Physics. - 2015.

Annotation:

Results from studying the amplitude response of PMTs and estimating the probability of correctly determining the direction of a particle track using quasispherical modules for different water transparencies and detection thresholds are described. Events are selected by the scintillation counters of the system of calibration telescopes and supermodules of the DECOR coordinate-tracking detector. Experimental data obtained before and after the startup of a new water purification system are used in the analysis. © 2015, Allerton Press, Inc.

Investigation of cascade showers in the Cherenkov water detector NEVOD / Mannocchi,G. / Journal of Physics: Conference Series. - 2015.

Annotation:

A technique for the reconstruction of cascade profiles by means of Cherenkov radiation in the water of the NEVOD detector is discussed. NEVOD is equipped with a dense spatial lattice of optical modules. The analyzed cascades have been generated either along near-horizontal muons (zenith angles between 85 and 90°), which's tracks are reconstructed by means of the tracking detector DECOR, or by muons with unknown tracks over a wider zenith angle range of 50-90°. Mean cascade profiles and energy spectra of cascades measured during the experimental series of about 7950 hours of 'live time' are presented. © Published under licence by IOP Publishing Ltd.

Investigation of Coherent Neutrino Scattering at the Spallation Neutron Source / Akimov,D.Yu. / Physics Procedia. - 2015.

Annotation:

We propose to observe and to study neutrino coherent scattering reaction at Spallation Neutron Source accelerator facility of the Oak Ridge National Laboratory (U.S.A.) using two-phase liquid xenon emission detector. We present expected detector rates for different experimental conditions. © 2015 The Authors.

Investigation of microstructure changes in ODS-EUROFER after hydrogen loading / Malitskii,E. / Journal of Nuclear Materials. - 2015.

Annotation:

The effect of hydrogen on the microstructure of mechanically tested ODS-EUROFER steel was investigated by means of transmission electron microscopy, thermal desorption spectroscopy, and atomistic simulations. The presence of yttrium oxide particles notably increases hydrogen uptake in ODS-EUROFER steel as compared to ODS-free EUROFER 97. Under tensile loading, hydrogen accumulation promotes the loss of cohesion at the oxide particle interfaces. First-principles molecular dynamics simulations indicate that hydrogen can be trapped at nanoparticle/matrix interface, creating OH-groups. The accumulation of hydrogen atoms at the oxide particle surface can be the reason for the observed hydrogen-induced oxide/matrix interface weakening and de-cohesion under the action of external tensile stress. © 2015 Elsevier B.V.

Investigation of nanostructure formation of alumina by magnetic pulse compression and subsequent spark plasma sintering / Kovaleva,I.V. / Physics Procedia. - 2015.

Annotation:

Comparative analysis of the structure and properties of samples prepared from alumina nanopowder using conventional or magnetic pulse compression (MPC), and the subsequent spark plasma sintering (SPS) was performed. In sintered corundum first identified the presence of areas with bimodal structure and the regularities of their formation. It was concluded that one of the most promising technologies for creating nanostructured ceramics is the application of the MPC and the SPS. Alumina submicron structure was obtained with a grain size of about 200-300 nm. The relative density of these samples determined by hydrostatic method was 95-96% of the theoretical. © 2015 Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license.

Investigation of the mechanism of conductivity of NbN thin films, modified under composite ion beam irradiation / Gurovich,B.A. [/ Micro and Nanosystems. - 2015.

Annotation:

The paper considers the use of low-energy composite ion beam radiation to change the superconducting properties of ultrathin (5 nm) films of niobium nitride. It was found that the effect of ion irradiation causes a reduction in the superconducting transition temperature and increasing the resistivity of the film in the normal state. We studied the electrical properties of the irradiated films with doses up to 12.6 d.p.a. (for Nitrogen) in the temperature range from 2 to 300 K. It is found that at a temperature of 4.2 K films irradiated with doses of 12.6 d.p.a. and above showed electric conductivity mechanism corresponding to typical insulators, and irradiated in a dose range 1.8-9 d.p.a. exhibited electrical conductivity mechanism corresponding to metals. We considered the possibility to use the technique of selective changes in the atomic composition under ion beam irradiation to create the resistive elements for cryogenic temperatures. © 2015 Bentham Science Publishers.

Investigation of vanadium-based alloys corrosion resistance in liquid lithium / Borovitskaya,I.V. / Problems of Atomic Science and Technology, Series Thermonuclear Fusion. - 2015.

Annotation:

A major concern regarding the use of vanadium-based alloys for fusion reactor first wall/blanket systems is their activity against the non-metallic impurities in the coolant. This paper presents the results of study of corrosion resistance in the liquid high purity lithium (con-tents of nitrogen and carbon less than 10-3% wt.) of vanadium and vanadium alloys (V-1.86Ga, V-3.4Ga-0.62Si, V-4.81Ti-4.82Cr) both non-irradiated and previously irradiated by 20 keV Ar+ ions up to dose of 1022 m-2 at the temperature of exposure 400 C. Corrosion tests were carried out in the static isothermal conditions at the temperature of 600 C during 400 hours. The corrosion behavior was evaluated by measuring weight and microhardness changes. The identity of the mechanisms of corrosion both irradiated and non-irradiated materials has been established, which consisted in the insignificant penetration of nitrogen into materials and significant oxy-gen transfer from materials into the lithium, what causes the formation of zones with reduced microhardness near the surface of samples. Traces of corrosion effect on the surface morphology of the studied materials after exposure to lithium were also found, resulting in the appearance of grain boundaries and slip lines, the latter being most clearly observed in the case of prelimanary irradiation by argon ions.

Is the standard model saved asymptotically by conformal symmetry? / Gorsky,A. / Journal of Experimental and Theoretical Physics. - 2015.

Annotation:

It is pointed out that the top-quark and Higgs masses and the Higgs VEV with great accuracy satisfy the relations 4minfH/inf sup2/sup = 2minfT/inf sup2/sup = vsup2/sup, which are very special and reminiscent of analogous ones at Argyres-Douglas points with enhanced conformal symmetry. Furthermore, the RG evolution of the corresponding Higgs self-interaction and Yukawa couplings λ(0) = 1/8 and y(0) = 1 leads to the free-field stable point $$(M_Pl ) = (M_Pl )$$ in the pure scalar sector at the Planck scale, also suggesting enhanced conformal symmetry. Thus, it is conceivable that the Standard Model is the low-energy limit of a distinct special theory with (super?) conformal symmetry at the Planck scale. In the context of such a “scenario,” one may further speculate that the Higgs particle is the Goldstone boson of (partly) spontaneously broken conformal symmetry. This would simultaneously resolve the hierarchy and Landau pole problems in the scalar sector and would provide a nearly flat potential with two almost degenerate minima at the electroweak and Planck scales. © 2015, Pleiades Publishing, Inc.

Isolation of flow and nonflow correlations by two- and four-particle cumulant measurements of azimuthal harmonics in sNN=200GeV Au+Au collisions / Abdelwahab,N.M. / Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 2015.

Annotation:

A data-driven method was applied to Au+Au collisions at sNN=200GeV made with the STAR detector at RHIC to isolate pseudorapidity distance δη-dependent and δη-independent correlations by using two- and four-particle azimuthal cumulant measurements. We identified a δη-independent component of the correlation, which is dominated by anisotropic flow and flow fluctuations. It was also found to be independent of η within the measured range of pseudorapidity |η|<1. In 20-30% central Au+Au collisions, the relative flow fluctuation was found to be 34%±2%(stat.)±3%(sys.) for particles with transverse momentum pinfT/inf less than 2 GeV/c. The δη-dependent part, attributed to nonflow correlations, is found to be 5%±2%(sys.) relative to the flow of the measured second harmonic cumulant at |δη|>0.7. © 2015 The Authors.

Isotopically modified molybdenum: Production for application in nuclear energy / Smirnov,A.Yu. / Physics Procedia. - 2015.

Annotation:

The possibility to use the isotopically modified molybdenum as a constructive material for the fuel rods of light water and fast reactors is discussed. The calculations demonstrate that the isotopically modified molybdenum with an average neutron absorption cross-section comparable to that of zirconium can be obtained with the reasonable for practice cost by a cascade of gas centrifuges, specially designed for separation of non-uranium isotopes. © 2015 Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license.

Itoyama,H. Matching branches of a nonperturbative conformal block at its singularity divisor / Itoyama,H., Mironov,A.D., Morozov,A.Y. / Theoretical and Mathematical Physics(Russian Federation). - 2015.

Annotation:

A conformal block is a function of many variables, usually represented as a formal series with coefficients that are certain matrix elements in the chiral (i.e., Virasoro) algebra. A nonperturbative conformal block is a multivalued function defined globally over the space of dimensions and has many branches and, perhaps, additional free parameters not seen at the perturbative level. We discuss additional complications of the nonperturbative description that arise because all the best-studied examples of conformal blocks are at the singularity locus in the moduli space (at divisors of the coefficients or, simply, at zeros of the Kac determinant). A typical example is the Ashkin-Teller point, where at least two naive nonperturbative expressions are provided by the elliptic Dotsenko-Fateev integral and by the celebrated Zamolodchikov formula in terms of theta constants, and they differ. The situation is somewhat similar at the Ising and other minimal model points. © 2015, Pleiades Publishing, Ltd.

Ivanov,Yu.B. Directed flow indicates a cross-over deconfinement transition in relativistic nuclear collisions / Ivanov,YuB, Soldatov,AA / PHYSICAL REVIEW C. - 2015.

Annotation:

Analysis of directed flow (v(1)) of protons, antiprotons, and pions in heavy-ion collisions is performed in the range of incident energiesv root(NN)-N-S = 2.7-27 GeV. Simulations have been done within a three-fluid model employing a purely hadronic equation of state (EoS) and two versions of the EoS involving deconfinement transitions: a first-order phase transition and a smooth crossover transition. High sensitivity of the directed flow, especially the proton one, to the EoS is found. The crossover EoS is favored by the most part of considered experimental data. A strong wiggle in the excitation function of the proton v(1) slope at the midrapidity obtained with the first-order-phase-transition EoS and a smooth proton v(1) with positive midrapidity slope, within the hadronic EoS unambiguously disagree with the data. The pion and antiproton v(1) also definitely testify in favor of the crossover EoS. The results obtained with deconfinement EoS's apparently indicate that these EoS's in the quark-gluon sector should be stiffer at high baryon densities than those used in the calculation.

Ivanov,Yu.B. Elliptic flow in heavy-ion collisions at energies root(NN)-N-S=2.7-39 GeV / Ivanov,YuB, Soldatov,AA / PHYSICAL REVIEW C. - 2015.

Annotation:

The transverse-momentum-integrated elliptic flow of charged particles at midrapidity, v(2)(charged), and that of identified hadrons from Au + Au collisions are computed in a wide range of incident energies 2.7

Jet energy measurement and its systematic uncertainty in proton–proton collisions at vs=7TeV with the ATLAS detector / AtlasCollaboration / European Physical Journal C. - 2015.

Annotation:

The jet energy scale (JES) and its systematic uncertainty are determined for jets measured with the ATLAS detector using proton–proton collision data with a centre-of-mass energy of (Formula presented.)(Formula presented.)TeV corresponding to an integrated luminosity of (Formula presented.)(Formula presented.)(Formula presented.)(Formula presented.). Jets are reconstructed from energy deposits forming topological clusters of alorimeter cells using the anti-(Formula presented.)(Formula presented.) algorithm with distance parameters (Formula presented.)(Formula presented.) or (Formula presented.)(Formula presented.), and are calibrated using MC simulations. A residual JES correction is applied to account for differences between data and MC simulations. This correction and its systematic uncertainty are estimated using a combination of in situ techniques exploiting the transverse momentum balance between a jet and a reference object such as a photon or a (Formula presented.)(Formula presented.) boson, for (Formula presented.)(Formula presented.) and pseudorapidities (Formula presented.)(Formula presented.). The effect of multiple proton–proton interactions is corrected for, and an uncertainty is evaluated using in situ techniques. The smallest JES uncertainty of less than 1 % is found in the central calorimeter region ((Formula presented.)(Formula presented.)) for jets with (Formula presented.)(Formula presented.). For central jets at lower (Formula presented.)(Formula presented.), the uncertainty is about 3 %. A consistent JES estimate is found using measurements of the calorimeter response of single hadrons in proton–proton collisions and test-beam data, which also provide the estimate for (Formula presented.)(Formula presented.) TeV. The calibration of forward jets is derived from dijet (Formula presented.)(Formula presented.) balance measurements. The resulting uncertainty reaches its largest value of 6 % for low-(Formula presented.)(Formula presented.) jets at (Formula presented.)(Formula presented.). Additional JES uncertainties due to specific event topologies, such as close-by jets or selections of event samples with an enhanced content of jets originating from light quarks or gluons, are also discussed. The magnitude of these uncertainties depends on the event sample used in a given physics analysis, but typically amounts to 0.5–3 %.

Kardashev,B.K. Low-temperature embrittlement and fracture of metals with different crystal lattices - Dislocation mechanisms / Kardashev,B.K., Moroz,K.A., Chernov,V.M. / Nuclear Materials and Energy. - 2015

Annotation:

The state of a low-temperature embrittlement (cold brittleness) and dislocation mechanisms for formation of the temperature of a ductile-brittle transition and brittle fracture of metals (mono- and polycrystals) with various crystal lattices (BCC, FCC, HCP) are considered. The conditions for their formation connected with a stress-deformed state and strength (low temperature yield strength) as well as the fracture breaking stress and mobility of dislocations in the top of a crack of the fractured metal are determined. These conditions can be met for BCC and some HCP metals in the initial state (without irradiation) and after a low-temperature damaging (neutron) irradiation. These conditions are not met for FCC and many HCP metals. In the process of the damaging (neutron) irradiation such conditions are not met also and the state of low-temperature embrittlement of metals is absent (suppressed) due to arising various radiation dynamic processes, which increase the mobility of dislocations and worsen the strength characteristics. © 2016 The Authors.

Karelin,A.V. Observation of the Moon's shadow in cosmic rays with energies above 400 GeV in the PAMELA satellite experiment / Karelin,AV, Voronov,SA, Koldobskiy,SA / COSMIC RESEARCH. - 2015.

Annotation:

Based on data obtained from satellite in 2006-2009 in the PAMELA experiment, the Moon's shadow was discovered in cosmic rays with energies above 400 GeV. The obtained results are based on using the method for determining the particle arrival direction in the position-sensitive calorimeter, which is part of the PAMELA magnetic spectrometer. The Moon's shadow was found to be shifted to the east due to deviations of electrons in the Earth's magnetic field, which are part of the sample of detected particles.

Khlopov,M. Cosmological probes for supersymmetry / Khlopov,M. / Symmetry. - 2015.

Annotation:

The multi-parameter character of supersymmetric dark-matter models implies the combination of their experimental studies with astrophysical and cosmological probes. The physics of the early Universe provides nontrivial effects of non-equilibrium particles and primordial cosmological structures. Primordial black holes (PBHs) are a profound signature of such structures that may arise as a cosmological consequence of supersymmetric (SUSY) models. SUSY-based mechanisms of baryosynthesis can lead to the possibility of antimatter domains in a baryon asymmetric Universe. In the context of cosmoparticle physics, which studies the fundamental relationship of the micro- and macro-worlds, the development of SUSY illustrates the main principles of this approach, as the physical basis of the modern cosmology provides cross-disciplinary tests in physical and astronomical studies. © 2015 by the authors.

Khlopov,M Cosmoparticle physics: The universe as a laboratory of elementary particles / Khlopov,M / ASTRONOMY REPORTS. - 2015.

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The development of Zeldovich's ideas on the cosmological impact of particle theory is discussed in the context of cosmoparticle physics, studying fundamental relationship of macro- and micro-worlds.

Khramtsova,T.P. Mutual disorientation texture in α-Zr polycrystals / Khramtsova,T.P., Skrytnyy,V.I., Yaltsev,V.N. / Non-ferrous Metals. - 2015.

Annotation:

Consideration of orientation distribution function makes it possible to investigate the orientation-dependent properties of polycrystalline materials. However, it is necessary to know the mutual disorientations of neighboring grains to describe such properties as grain-boundary diffusion, grain-boundary migration and slipping along the grain boundaries. Application of disorientation matrices allows to construct a disorientation distribution function both in angle-axis crystallographic space and in Euler space. This method was applied for rolled polycrystalline α-zirconium. In particular, mutual disorientations do not fill the whole space, which leads to the possibility of appearance of mutual disorientations, texture in rolled polycrystalline α-zirconium. The physicomechanical properties of polycrystalline materials are determined both by the properties and orientation of individual grains and grain boundaries. For the purpose of description of orientation relationships between the crystals, it is necessary to consider the orientation distribution function. Since the mutual disorientation of two grains can be specified by rotation angle (α), rotation axis (l), or by Euler angles (φ, θ, and ψ), then mutual disorientations, texture can be considered either in angle-axis crystallographic space or in Euler space. Mutual disorientation of two neighboring crystals is described as the turn of a crystal relative to another one by the disorientation matrix R = Ainf2/inf; sup-1/sup·Ainf1/inf (where Ainf2/inf and Ainf1/inf are orientation matrices of crystals). Because of the crystal lattice symmetry, disorientation can be described by physically equivalent turns with matrices Rinfi/inf = RCinfi/inf; sup-1/sup, where Cinfi/inf is the turning element of the crystal symmetry. The data about mutual disorientation distribution function of crystals for α-zirconium are presented both in Euler space and in "angle α - axis l" space.

Kitayev,I.N. Two-tone ion-acoustic waves in degenerate quantum plasma / Kitayev,I.N., Dubinov,A.E. / Physics of Wave Phenomena. - 2015.

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Ion-acoustic waves (IAWs) in a quantum electron-ion plasma with degenerate components are theoretically investigated using a system of quantum equations of gas dynamics that allow for the quantum-size character of the object (Bohm’s quantum force is included in the equation of motion) and the Pauli exclusion principle (equations of state for degenerate Fermi gases of electrons and ions are used). Linear analysis and numerical solution of equations yielded an identical qualitative result: periodic IAWs in a quantum electron-ion plasma are always a superposition of two waves with equal phase velocities but different wavelengths. The high-frequency component of the IAW is identified with free quantum oscillations of ions. A solution in the form of an ion-sound soliton with free quantum oscillations of ions superposed on its profile is also found. © 2015, Allerton Press, Inc.

Knot invariants from Virasoro related representation and pretzel knots / Galakhov,D. / Nuclear Physics B. - 2015.

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We remind the method to calculate colored Jones polynomials for the plat representations of knot diagrams from the knowledge of modular transformation (monodromies) of Virasoro conformal blocks with insertions of degenerate fields. As an illustration we use a rich family of pretzel knots, lying on a surface of arbitrary genus g, which was recently analyzed by the evolution method. Further generalizations can be to generic Virasoro modular transformations, provided by integral kernels, which can lead to the Hikami invariants. © 2015 The Authors.

Kochnov,O.Y. Improvement of the Neutron-Physical Characteristics of the VVR-Ts Reactor by Substituting a Beryllium Reflector for Some Fuel Assemblies in the Core / Kochnov,O.Y., Kolesov,V.V., Fomin,R.V. / Atomic Energy. - 2015.

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The results of computational studies of the possibility of using beryllium reflectors to improve the neutronphysical characteristics of the VVR-Ts reactor, which is used at the Karpov Research Institute of Physical Chemistry to produce radionuclides, are presented. The calculations showed that in principle beryllium can be used by substituting it for some number of standard fuel assemblies. This made it possible to decrease the number of fuel assemblies from 70 in the standard core to 59 in a modified core and increase the run time to 14 days. The calculations also indicate that the neutron flux density in the experimental channels can be increased significantly, which is important for increasing the production of radionuclides. The [InlineMediaObject not available: see fulltext.]hermophysical aspects of the modified core are not studied. © 2015 Springer Science+Business Media New York

Koldobskiy,S.A. The Development of Tritium Identification Method for the PAMELA Experiment / Koldobskiy,S.A., Valieva,A.A., Voronov,S.A. / Physics Procedia. - 2015.

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This article focuses on the development of the method of cosmic ray tritium nuclei identification based on data of the PAMELA experiment which is installed on board satellite Resurs-DK1. The tritium nuclei identification was implemented by measuring the particle rigidity and velocity, as well as energy losses in the tracker detectors. We discuss the method of tritium separation on the background of other nuclei. The criteria for event selection allow distinguishing tritium nuclei in the magnetic rigidity range 0.5 - 3.0 GV. © 2015 The Authors.

Kononov,Y. Colored HOMFLY and generalized Mandelbrot set / Kononov,Y., Morozov,A. / Journal of High Energy Physics. - 2015.

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Abstract: Mandelbrot set is a closure of the set of zeroes of resultant x (Fn, Fm) for iterated maps Fn(x) = f °n(x) − x in the moduli space of maps f (x). The wonderful fact is that for a given n all zeroes are not chaotically scattered around the moduli space, but lie on smooth curves, with just a few cusps, located at zeroes of discriminant x (Fn). We call this phenomenon the Mandelbrot property. If approached by the cabling method, symmetrically-colored HOMFLY polynomials Hn K(A|q) can be considered as linear forms on the n-th “power” of the knot K, and one can wonder if zeroes of resultant q 2 (Hn, Hm) can also possess the Mandelbrot property. We present and discuss such resultant-zeroes patterns in the complex-A plane. Though A is hardly an adequate parameter to describe the moduli space of knots, the Mandelbrot-like structure is clearly seen — in full accord with the vision of hep-th/0501235, that concrete slicing of the Universal Mandelbrot set is not essential for revealing its structure. © 2015, The Author(s).

Kononov,Y. Factorization of colored knot polynomials at roots of unity / Kononov,Y., Morozov,A. / Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 2015.

Annotation:

HOMFLY polynomials are the Wilson-loop averages in Chern-Simons theory and depend on four variables: the closed line (knot) in 3d space-time, representation R of the gauge group SU(N) and exponentiated coupling constant q. From analysis of a big variety of different knots we conclude that at q, which is a 2m-th root of unity, qsup2m/sup=1, HOMFLY polynomials in symmetric representations [r] satisfy recursion identity: Hinfr+m/inf=Hinfr/infdot operatorHinfm/inf for any A=qsupN/sup, which is a generalization of the property Hr=H1r for special polynomials at m=1. We conjecture a further generalization to arbitrary representation R, which, however, is checked only for torus knots. Next, Kashaev polynomial, which arises from HinfR/inf at qsup2/sup=esup2πi/|R|/sup, turns equal to the special polynomial with A substituted by Asup|R|/sup, provided R is a single-hook representations (including arbitrary symmetric) - what provides a q-A dual to the similar property of Alexander polynomial. All this implies non-trivial relations for the coefficients of the differential expansions, which are believed to provide reasonable coordinates in the space of knots - existence of such universal relations means that these variables are still not unconstrained. © 2015 Published by Elsevier B.V.

Kononov,Y. On the defect and stability of differential expansion / Kononov,Y., Morozov,A. / JETP Letters. - 2015.

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Empirical analysis of many colored knot polynomials, made possible by recent computational advances in Chern–Simons theory, reveals their stability: for any given negative N and any given knot the set of coefficients of the polynomial in rth symmetric representation does not change with r, if it is large enough. This fact reflects the non-trivial and previously unknown properties of the differential expansion, and it turns out that from this point of view there are universality classes of knots, characterized by a single integer, which we call defect, and which is in fact related to the power of Alexander polynomial. © 2015, Pleiades Publishing, Inc.

Konoplich,R.V. Cosmological implications of Higgs field fluctuations during inflation / Konoplich,R.V., Grobov,A.V., Rubin,S.G. / Annalen der Physik. - 2015.

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Cosmological implications of Higgs field fluctuations during inflation are considered. This study is based on the Standard Model and the standard quadratic model of chaotic inflation where the Higgs field is minimally coupled to gravity and has no direct coupling to the inflaton. In the Standard model the renormalisation group improved effective potential develops an instability (an additional minimum and maximum) at large field values. It is shown that such a new maximum should take place at an energy scale above 1014GeV, otherwise a universe like ours is extremely unlikely. The extension to the case of the Higgs field interacting with the inflaton field is discussed. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA.

Korolyov,P.A. Magnetic wormholes and black universes with invisible ghosts / Korolyov,P.A., Bronnikov,K.A. / Gravitation and Cosmology. - 2015.

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We construct explicit examples of globally regular static, spherically symmetric solutions in general relativity with scalar and electromagnetic fields describing traversable wormholes with flat and AdS asymptotics and regular black holes, in particular, black universes. (A black universe is a regular black hole with an expanding, asymptotically isotropic space-time beyond the horizon.) The existence of such objects requires invoking scalars with negative kinetic energy (“phantoms, ” or “ghosts”), which are not observed under usual physical conditions. To account for that, the so-called “trapped ghosts” were previously introduced, i.e., scalars whose kinetic energy is only negative in a restricted strong-field region of space-time and positive outside it. This approach leads to certain problems, including instability (as is illustrated here by derivation of an effective potential for spherical pertubations of such systems). In this paper, we use for model construction what we call “invisible ghosts, ” i.e., phantom scalar fields sufficiently rapidly decaying in the weak-field region. The resulting configurations contain different numbers of Killing horizons, from zero to four. © 2015, Pleiades Publishing, Ltd.

Kravchenko,P.D. New approaches to the substantiation of the concept of optimum of the technological process of manufacturing facilities of atomic power engineering / Kravchenko,P.D. / International Journal of Applied Engineering Research. - 2015.

Annotation:

The article considers the new approaches while substantiationing the conception of an optimal technological fabrication process of heavy large-sized case-shaped constructions of atomic power engineering. The WTFM- «work piece - tool- fixture-machine» system is proposed instead of known MFTW system - «machine- fixture-tool-work piece». This system makes it possible to use small-sized mobile technological equipment that can be located on the processed object and used as the base instead of using heavy large-sized technological equipment. Exemplary drawings of modern and proposed processes with technological equipment using in the course of the machining process and relocation of the objects are shown. The example of using heuristic methods during the projection of technological processes with technological equipment that are used in the course of the machining process and relocation of the objects with the use of wildlife examples- «the principle of a spider», «the principle of an ant», «the principle of a beaver». The use of well-grounded factors of quality during the projection of technological process allows minimizing decision makers influence in the course of the projection. © Research India Publications.

Kudryavtsev,A.V. Modernization of the RBMK fuel assemblies cladding tightness monitoring system / Kudryavtsev,A.V., Mokhnonozhkin,B.E., Fedorov,V.A. / 9th International Topical Meeting on Nuclear Plant Instrumentation, Control, and Human-Machine Interface Technologies, NPIC and HMIT 2015. - 2015.

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Results of modernization of the system monitoring tightness cladding of the nuclear reactor RBMK based on contemporary hardware and software are presented. The article describes purpose, structure and features of the old system leakage testing. The need of system modernization is discussed. The stages of modernization, structure, characteristics of the new system, applied technical solutions, advanced features, and also search methods of leaky fuel assemblies are described. The advantages of the upgraded system, the results of the implementation and operation phases are provided.

Kulikov,E.G. Visualization as a tool for plutonium proliferation protection assessment / Kulikov,E.G. / Scientific Visualization. - 2015.

Annotation:

The advancement of the nuclear power industry can come together with nuclear materials suitable both for peaceful and military applications circle. So, mathematical methodologies should be developed for the correct resolution of the following problem: what nuclear materials could be recognized as proliferation protected ones, i.e. what nuclear materials are unsuitable for manufacturing a nuclear explosive device (NED). As known, there are two fundamentally different types of NED: guntype and implosiontype [1]. The computationaltheoretical model of guntype device has been considered in author's previous paper [2]. In the present paper computationaltheoretical model has been developed and visualized, which aims at quantitative assessment of plutonium proliferation protection against creating implosiontype hypothetical nuclear explosive device (HNED). The main nuclearphysical and thermal processes that occur in implosiontype HNED are being modeled. The model allows us to develop requirements that guarantee nonfunctionality of implosiontype HNED. This is achieved by introducing radioactive isotope (sup238/supPu) into plutonium, the heat of alphadecay of which could overheat HNED and render it nonfunctional. The present paper is an essential development of previous works devoted to plutonium proliferation protection. Firstly, it has been demonstrated that it is necessary to analyze the transient warmingup process of implosiontype HNED to determine how soon such a device loses its functionality taking into account various compositions of plutonium and other materials used, as well as different methods of heat dissipation. Secondly, the possibility has been analyzed to slow down warmingup process of implosiontype HNED by means of: · preliminary cooling of HNED components; · encircling of HNED with a heat sink layer; · introducing thermal isolating interlayers into HNED structure for purposeful redistribution of temperature field in such a way when device keeps its functionality the longest. These aspects are not only fundamentally new, but extremely important, as they affect plutonium proliferation protection estimations drastically (several times difference). As plutonium proliferation protection issues concern not only engineers, but also representatives of some of the humanities, visualization of these issues is essential. Moreover, the material presented in such a form is much easier for students to understand.

Kushin,V.V. A study of the CR-39 track detector sensitivity to heavy charged particles of space radiation / Kushin,V.V., Inozemtsev,K.O. / Instruments and Experimental Techniques. - 2015.

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The sensitivity of the 1-mm-thick solid-state CR-39 TASTRAK track detector to space radiation particles in a wide linear energy transfer range, α particles with energies near the Bragg peak, and accelerated sup39/supAr nuclei with different angles of incidence has been measured. Various approaches to track scanning and data processing algorithms were used to measure the sensitivity. Comparative analysis of experimental results is presented. Practical recommendations on the application of obtained results for evaluation of nuclear track detectors exposed in low-Earth orbit were developed. © 2015, Pleiades Publishing, Inc.

Kuz’min,A.M. Sensitivity of Optimal Design Problem Solutions for Nuclear Reactors to a Change in the Input Parameters / Kuz’min,A.M. / Atomic Energy. - 2015.

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Methods for analyzing the sensitivity of the optimal values of target functionals and controlling parameters to small changes in the initial data in optimization problems for nuclear reactors are examined. The computational aspects and particularities of the methods are discussed. As an example the sensitivity of the solution to the problem of minimizing the specific mass of nuclear fuel present in the fuel cycle of a gas-cooled fast reactor to a change in the coolant density is investigated. © 2015 Springer Science+Business Media New York

K∗(892)0 and φ(1020) production in Pb-Pb collisions at sNN =2.76 TeV / Abelev,B. / Physical Review C - Nuclear Physics. - 2015.

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The yields of the K∗(892)0 and φ(1020) resonances are measured in Pb-Pb collisions at sNN=2.76 TeV through their hadronic decays using the ALICE detector. The measurements are performed in multiple centrality intervals at mid-rapidity (|y|<0.5) in the transverse-momentum ranges 0.3<pT<5 GeV/c for the K∗(892)0 and 0.5<pT<5 GeV/c for the φ(1020). The yields of K∗(892)0 are suppressed in central Pb-Pb collisions with respect to pp and peripheral Pb-Pb collisions (perhaps due to rescattering of its decay products in the hadronic medium), while the longer-lived φ(1020) meson is not suppressed. These particles are also used as probes to study the mechanisms of particle production. The shape of the pT distribution of the φ(1020) meson, but not its yield, is reproduced fairly well by hydrodynamic models for central Pb-Pb collisions. In central Pb-Pb collisions at low and intermediate pT, the p/φ(1020) ratio is flat in pT, while the p/π and φ(1020)/π ratios show a pronounced increase and have similar shapes to each other. These results indicate that the shapes of the pT distributions of these particles in central Pb-Pb collisions are determined predominantly by the particle masses and radial flow. Finally, φ(1020) production in Pb-Pb collisions is enhanced, with respect to the yield in pp collisions and the yield of charged pions, by an amount similar to the Λ and Ξ.

Limits on the Higgs boson lifetime and width from its decay to four charged leptons / Khachatryan,V. / Physical Review D - Particles, Fields, Gravitation and Cosmology. - 2015.

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Constraints on the lifetime and width of the Higgs boson are obtained from H→ZZ→4ℓ events using data recorded by the CMS experiment during the LHC run 1 with an integrated luminosity of 5.1 and 19.7fb-1 at a center-of-mass energy of 7 and 8 TeV, respectively. The measurement of the Higgs boson lifetime is derived from its flight distance in the CMS detector with an upper bound of τH<1.9×10-13s at the 95% confidence level (C.L.), corresponding to a lower bound on the width of ΓH>3.5×10-9MeV. The measurement of the width is obtained from an off-shell production technique, generalized to include anomalous couplings of the Higgs boson to two electroweak bosons. From this measurement, a joint constraint is set on the Higgs boson width and a parameter fΛQ that expresses an anomalous coupling contribution as an on-shell cross-section fraction. The limit on the Higgs boson width is ΓH<46MeV with fΛQ unconstrained and ΓH<26MeV for fΛQ=0 at the 95% C.L. The constraint fΛQ<3.8×10-3 at the 95% C.L. is obtained for the expected standard model Higgs boson width. © 2015 CERN, for the CMS. Published by the American Physical Society.

Local anisotropy of muon flux - The basis of the method of muon diagnostics of extra-terrestrial space / Astapov,I.I. / Advances in Space Research. - 2015.

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A new method for the analysis of spatial and angular characteristics of the cosmic ray muon flux registered in the hodoscopic mode using a single setup - the muon hodoscope - is presented. Various parameters of the muon flux anisotropy and methods of calculation of these parameters are discussed. It is shown that the horizontal projection of the muon flux relative anisotropy vector which characterizes lateral (horizontal) displacement of the muon flux angular distribution is the sensitive parameter to a variety of nonstationary processes in the heliosphere. The experimental data on the variation of the muon flux anisotropy during the passage of various irregularities in the solar wind and interplanetary magnetic field in the Earth's vicinity are presented. © 2015 COSPAR.

Local anisotropy of muon flux during Forbush decreases from URAGAN data / Mannocchi,G. / Journal of Physics: Conference Series. - 2015.

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The approach to the analysis of spatial-angular characteristics of the muon flux variations at different phases of Forbush decrease development according to the muon snapshots (muongraphies) obtained using muon hodoscope URAGAN, as well as the analysis results are presented. © Published under licence by IOP Publishing Ltd.

Long-range pseudorapidity dihadron correlations in d + Au collisions at √sNN = 200 GeV / Adamczyk,L. / Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 2015.

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Dihadron angular correlations in d + Au collisions at √sNN = 200 GeV are reported as a function of the measured zero-degree calorimeter neutral energy and the forward charged hadron multiplicity in the Au-beam direction. A finite correlated yield is observed at large relative pseudorapidity (δη) on the near side (i.e. relative azimuth δϕ~0). This correlated yield as a function of δη appears to scale with the dominant, primarily jet-related, away-side (δϕ~π) yield. The Fourier coefficients of the δϕ correlation, Vinfn/inf=〈cos n δ ϕ〉, have a strong δη dependence. In addition, it is found that Vinf1/inf is approximately inversely proportional to the mid-rapidity event multiplicity, while Vinf2/inf is independent of it with similar magnitude in the forward (d-going) and backward (Au-going) directions. © 2015 The Authors.

Looking for antineutrino flux from 40K with large liquid scintillator detector / Sinev,V.V. / Physics of Particles and Nuclei. - 2015.

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We regard the possibility of detecting the antineutrino flux producing by the 40K placing inside the Earth. Thermal flux of the Earth could be better understood with observing such a flux. Lower and upper limitations on the 40K antineutrino flux are presented.

Low-energy (anti)neutrino physics with Borexino: Neutrinos from the primary proton-proton fusion process in the Sun / Mosteiro,P. / Nuclear and Particle Physics Proceedings. - 2015.

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The Sun is fueled by a series of nuclear reactions that produce the energy that makes it shine. The primary reaction is the fusion of two protons into a deuteron, a positron and a neutrino. These neutrinos constitute the vast majority of neutrinos reaching Earth, providing us with key information about what goes on at the core of our star. Several experiments have now confirmed the observation of neutrino oscillations by detecting neutrinos from secondary nuclear processes in the Sun; this is the first direct spectral measurement of the neutrinos from the keystone proton-proton fusion. This observation is a crucial step towards the completion of the spectroscopy of pp-chain neutrinos, as well as further validation of the LMA-MSW model of neutrino oscillations. © 2015 Elsevier B.V.

Machulin,I.N. Geoneutrinos / Machulin,I.N. / Physics of Atomic Nuclei. - 2015.

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Academician M.A. Markov in the 1960s first proposed detecting the electron antineutrino in the reaction of inverse beta decay on a proton to study the processes inside the Earth. The radioactive isotopes sup238/supU, sup232/supTh, and sup40/supK present in our planet decay with radiation of neutrinos (antineutrinos). Neutrinos that are produced reach the Earth’s surface practically without absorption and carry information about the internal structure of the planet. However, because of the smallness of the antineutrino fluxes and interaction cross sections with matter, antineutrinos of geological origin were first registered in only two experiments (Borexino and Kamland) in recent years. The experimental observation of antineutrinos from the isotope decays in the depths of the Earth is the only way to study the radiation in our planetary interior. © 2015, Pleiades Publishing, Ltd.

Magnetic polarizabilities of light mesons in SU(3) lattice gauge theory / Kochetkov,O.A. / Nuclear Physics B. - 2015.

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We investigate the ground state energies of neutral pseudoscalar and vector meson in SU(3) lattice gauge theory in the strong abelian magnetic field. The energy of ρsup0/sup meson with zero spin projection sinfz/inf=0 on the axis of the external magnetic field decreases, while the energies with non-zero spins sinfz/inf=-1 and +1 increase with the field. The energy of πsup0/sup meson decreases as a function of the magnetic field. We calculate the magnetic polarizabilities of pseudoscalar and vector mesons for lattice volume 18sup4/sup. For ρsup0/sup with spin |sinfz/inf|=1 and πsup0/sup meson the polarizabilities in the continuum limit have been evaluated. We do not observe any evidence in favour of tachyonic mode existence. © 2015 The Authors.

Magnetometer Application for GAMMA-400 Telescope Switching into the Mode with Increased Low Energy Charged Particles Intensity Registration / Topchiev,N.P. / Physics Procedia. - 2015.

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GAMMA-400 is an international project of a high apogee orbital astrophysical observatory for studying the characteristics of high-energy gamma-emission, electrons/positrons and light nuclei fluxes. The energy range for γ-rays and electrons/positrons registration in the main aperture is from 0.1 GeV to 3.0 TeV. Also, this aperture allows high energy light nuclei fluxes characteristics investigation. Moreover, special aperture configuration allows registering of gamma-quanta, electrons (positrons) and light nuclei from the lateral directions too. The spacecraft GAMMA-400 orbit will be located in the Earth's magnetosphere and will pass front shock wave from magnetosphere interaction with the solar wind, turbulent-transition region, magnetopause and so on. During the satellite's movement through various Earth's magnetosphere regions its anticoincidence detectors will register high intensity fluxes of low energy charged particles captured by the magnetic field. The working area sections of GAMMA-400 detector systems used as anticoincidence shield are about 1 m2 each. The high intensity low energy charged particles flux influence on anticoincidence detectors should be taken into account during particle identification. This article presents a comparison between Earth's magnetosphere theoretical model according to SPENVIIS package and real data measured by detectors onboard THEMIS series satellites. The differences between these two datasets indicate that the calculated data are not sufficient to make short time predictions of variations of magnetic induction in the outer magnetosphere. A special trigger marker flag will be produced by GAMMA-400 counting and triggers signals formation system accordingly to the data of two onboard magnetometers. This flag's presence leads to special algorithms execution start, putting the plastic detectors into a dedicated working mode taking into account possible high count rates of external detector layers. © 2015 The Authors.

Maximenko,A.L. Homogenization of Biporous Agglomerated Powder Structures During High-Temperature Consolidation / Maximenko,A.L., Olevsky,E.A., Grigoryev,E.G. / Journal of the American Ceramic Society. - 2015.

Annotation:

Specifics of agglomerate densification-important for hot pressing, conventional, and spark plasma sintering of powders-are analyzed based on the biporous material modeling framework. Numerical simulations are utilized to determine what technological parameters can be used to improve the postprocessing homogeneity of agglomerated powder-based materials. The modeling results indicate that the homogenization during sintering and hot pressing of agglomerated nano- and micrometer-size powders is significantly impacted by the viscosity of grain-boundary sliding and by the possible existence of high-intensity diffusion paths along the agglomerate boundaries. © 2015 The American Ceramic Society.

McGovern,JudithA Predictions of covariant chiral perturbation theory for nucleon polarisabilities and polarised Compton scattering / McGovern,JudithA, Pascalutsa,Vladimir, Lensky,Vadim / EUROPEAN PHYSICAL JOURNAL C. - 2015.

Annotation:

We update the predictions of the SU(2) baryon chiral perturbation theory for the dipole polarisabilities of the proton, alpha(E1), beta(M1)(p) = 11.2(0.7), 3.9(0.7) x 10(-4) fm(3), and obtain the corresponding predictions for the quadrupole, dispersive, and spin polarisabilities: alpha(E2), beta(M2)(p) = 17.3(3.9), -15.5(3.5) x 10(-4) fm(5), alpha(E1)., beta(M1).(p) = -1.3(1.0), 7.1(2.5) x 10(-4) fm(5), and gamma(E1E1), gamma(M1M1), gamma(E1M2), gamma(M1E2)(p) = -3.3(0.8), 2.9(1.5), 0.2(0.2), 1.1 (0.3) x 10(-4) fm(4). The results for the scalar polarisabilities are in significant disagreement with semi-empirical analyses based on dispersion relations; however, the results for the spin polarisabilities agree remarkably well. Results for proton Compton-scattering multipoles and polarised observables up to the Delta(1232) resonance region are presented too. The asymmetries Sigma(3) and Sigma(2x) reproduce the experimental data from LEGS and MAMI. Results for Sigma(2z) agree with a recent sum rule evaluation in the forward kinematics. The asymmetry Sigma(1z) near the pion production threshold shows a large sensitivity to chiral dynamics, but no data is available for this observable. We also provide the predictions for the polarisabilities of the neutron, the numerical values being alpha(E1), beta(M1)(n) = 13.7(3.1), 4.6(2.7) x 10(-4) fm(3), alpha(E2), beta(M2)(n) = 16.2(3.7), -15.8(3.6) x 10(-4) fm(5), alpha(E1 nu), beta(M1 nu)(n) = 0.1(1.0), 7.2(2.5) x 10(-4) fm(5), and gamma(E1E1), gamma(M1M1), gamma(E1M2), gamma(M1E2)(n) = -4.7(1.1), 2.9(1.5), 0.2(0.2), 1.6(0.4) x 10(-4) fm(4). The neutron dynamical polarisabilities and multipoles are examined too. We also discuss subtleties related to matching the dynamical and static polarisabilities.

Measurement of B-0 - (Ds-KS0)pi(+) and B+ - Ds-K+K+ branching fractions / Wiechczynski,J / PHYSICAL REVIEW D. - 2015.

Annotation:

We report a measurement of the B-0 and B+ meson decays to the (Ds-KS0)pi(+) and Ds-K+K+ final states, respectively, using 657 x 10(6)B (B) over bar pairs collected at the gamma(4S) resonance with the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider. Using the D-s(-) - phi pi(-), K*(892)K-0(-) and (KSK-)-K-0 decay modes for the D-s reconstruction, we measure the following branching fractions: B(B-0 - (Ds-KS0)pi(+))= [0.47 +/- 0.06(stat) +/- 0.05(syst)] x 10(-4) and B(B+ - Ds-K+K+)= [0.93 +/- 0.22(stat) +/- 0.10(syst)] x 10(-5). We find the ratio of the branching fraction of B+ - Ds-K+K+ to that of the analogous Cabibbo-favored B+ - Ds-K+pi(+) decay to be R-B= 0.054 +/- 0.013(stat) +/- 0.006(syst), which is consistent with the naive factorization model. We also observe a deviation of the DsK invariant-mass distribution from the three-body phase-space model for both studied decays.

Measurement of charged jet production cross sections and nuclear modification in p-Pb collisions at sNN=5.02 TeV / Adamová,D. / Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 2015.

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Charged jet production cross sections in p-Pb collisions at sNN=5.02 TeV measured with the ALICE detector at the LHC are presented. Using the anti-kinfT/inf algorithm, jets have been reconstructed in the central rapidity region from charged particles with resolution parameters R=0.2 and R=0.4. The reconstructed jets have been corrected for detector effects and the underlying event background. To calculate the nuclear modification factor, RinfpPb/inf, of charged jets in p-Pb collisions, a pp reference was constructed by scaling previously measured charged jet spectra at s=7 TeV. In the transverse momentum range 20≤pinfT,chjet/inf≤120 GeV/c, RinfpPb/inf is found to be consistent with unity, indicating the absence of strong nuclear matter effects on jet production. Major modifications to the radial jet structure are probed via the ratio of jet production cross sections reconstructed with the two different resolution parameters. This ratio is found to be similar to the measurement in pp collisions at s=7 TeV and to the expectations from PYTHIA pp simulations and NLO pQCD calculations at sNN=5.02 TeV. © 2015 CERN for the benefit of the ALICE Collaboration.

Measurement of charged-particle spectra in Pb+Pb collisions at (Formula presented.) = 2.76 TeV with the ATLAS detector at the LHC / TheATLAScollaboration / Journal of High Energy Physics. - 2015.

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Charged-particle spectra obtained in Pb+Pb interactions at (Formula presented.) and pp interactions at (Formula presented.) with the ATLAS detector at the LHC are presented, using data with integrated luminosities of 0.15 nbsup−1/sup and 4.2 pbsup−1/sup, respectively, in a wide transverse momentum (0.5 < pinfT/inf< 150 GeV) and pseudorapidity (|η| < 2) range. For Pb+Pb collisions, the spectra are presented as a function of collision centrality, which is determined by the response of the forward calorimeters located on both sides of the interaction point. The nuclear modification factors RinfAA/inf and RinfCP/inf are presented in detail as a function of centrality, pinfT/inf and η. They show a distinct pinfT/inf-dependence with a pronounced minimum at about 7 GeV. Above 60 GeV, RinfAA/inf is consistent with a plateau at a centrality-dependent value, within the uncertainties. The value is 0.55 ± 0.01(stat.) ± 0.04(syst.) in the most central collisions. The RinfAA/inf distribution is consistent with flat |η| dependence over the whole transverse momentum range in all centrality classes. © 2015, The Author(s).

Measurement of charm and beauty production at central rapidity versus charged-particle multiplicity in proton-proton collisions at √s = 7 TeV / TheALICEcollaboration / Journal of High Energy Physics. - 2015.

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Prompt D meson and non-prompt J/ψ yields are studied as a function of the multiplicity of charged particles produced in inelastic proton-proton collisions at a centre-of-mass energy of √ = 7 TeV. The results are reported as a ratio between yields in a given multiplicity interval normalised to the multiplicity-integrated ones (relative yields). They are shown as a function of the multiplicity of charged particles normalised to the average value for inelastic collisions (relative charged-particle multiplicity). Dsup0/sup, Dsup+/sup and Dsup*+/sup mesons are measured in five pinfT/inf intervals from 1 GeV/c to 20 GeV/c and for |y| < 0.5 via their hadronic decays. The D-meson relative yield is found to increase with increasing charged-particle multiplicity. For events with multiplicity six times higher than the average multiplicity of inelastic collisions, a yield enhancement of a factor about 15 relative to the multiplicity-integrated yield in inelastic collisions is observed. The yield enhancement is independent of transverse momentum within the uncertainties of the measurement. The Dsup0/sup-meson relative yield is also measured as a function of the relative multiplicity at forward pseudo-rapidity. The non-prompt J/ψ, i.e. the B hadron, contribution to the inclusive J/ψ production is measured in the di-electron decay channel at central rapidity. It is evaluated for pinfT/inf > 1.3 GeV/c and |y| < 0.9, and extrapolated to pinfT/inf > 0. The fraction of non-prompt J/ψ in the inclusive J/ψ yields shows no dependence on the charged-particle multiplicity at central rapidity. Charm and beauty hadron relative yields exhibit a similar increase with increasing charged-particle multiplicity. The measurements are compared to PYTHIA 8, EPOS 3 and percolation calculations. © 2015, The Author(s).

Measurement of colour flow with the jet pull angle in tt- events using the ATLAS detector at √s=8 TeV / Aad,G. / Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 2015.

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The distribution and orientation of energy inside jets is predicted to be an experimental handle on colour connections between the hard-scatter quarks and gluons initiating the jets. This Letter presents a measurement of the distribution of one such variable, the jet pull angle. The pull angle is measured for jets produced in tt- events with one W boson decaying leptonically and the other decaying to jets using 20.3 fbsup-1/sup of data recorded with the ATLAS detector at a centre-of-mass energy of s=8 TeV at the LHC. The jet pull angle distribution is corrected for detector resolution and acceptance effects and is compared to various models. © 2015 CERN for the benefit of the ATLAS Collaboration.

Measurement of differential J/ψ production cross sections and forward-backward ratios in p + Pb collisions with the ATLAS detector MEASUREMENT of DIFFERENTIAL J/ψ PRODUCTION ... G. AAD et al. / Aad,G. / Physical Review C - Nuclear Physics. - 2015.

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Measurements of differential cross sections for J/ψ production in p+Pb collisions at sNN=5.02 TeV at the CERN Large Hadron Collider with the ATLAS detector are presented. The data set used corresponds to an integrated luminosity of 28.1 nb-1. The J/ψ mesons are reconstructed in the dimuon decay channel over the transverse momentum range 8<pT<30GeV and over the center-of-mass rapidity range -2.87<y∗<1.94. Prompt J/ψ are separated from J/ψ resulting from b-hadron decays through an analysis of the distance between the J/ψ decay vertex and the event primary vertex. The differential cross section for production of nonprompt J/ψ is compared to a FONLL calculation that does not include nuclear effects. Forward-backward production ratios are presented and compared to theoretical predictions. These results complement previously published results by covering a region of higher transverse momentum and more central rapidity. They thus constrain the kinematic dependence of nuclear modifications of charmonium and b-quark production in p+Pb collisions. © 2015 CERN. ©2015 CERN, for the ATLAS Collaboration. Published by the American Physical Society under the terms of the Creative Commons Attribution 3.0 License. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.

Measurement of dijet kT in p-Pb collisions at √sNN=5.02 TeV / Adamovб,D. / Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 2015.

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A measurement of dijet correlations in p-Pb collisions at √sNN=5.02 TeV with the ALICE detector is presented. Jets are reconstructed from charged particles measured in the central tracking detectors and neutral energy deposited in the electromagnetic calorimeter. The transverse momentum of the full jet (clustered from charged and neutral constituents) and charged jet (clustered from charged particles only) is corrected event-by-event for the contribution of the underlying event, while corrections for underlying event fluctuations and finite detector resolution are applied on an inclusive basis. A projection of the dijet transverse momentum, kinfTy/inf=psupch+ne/sup; infT,jet/infsin(δϕinfdijet/inf) with δϕinfdijet/inf the azimuthal angle between a full and charged jet and psupch+ne/sup; infT,jet/inf the transverse momentum of the full jet, is used to study nuclear matter effects in p-Pb collisions. This observable is sensitive to the acoplanarity of dijet production and its potential modification in p-Pb collisions with respect to pp collisions. Measurements of the dijet kinfTy/inf as a function of the transverse momentum of the full and recoil charged jet, and the event multiplicity are presented. No significant modification of kinfTy/inf due to nuclear matter effects in p-Pb collisions with respect to the event multiplicity or a PYTHIA8 reference is observed. © 2015 CERN for the benefit of the ALICE Collaboration.

Measurement of e(+)e(-) - gamma chi(cJ) via initial state radiation at Belle / Han,YL / PHYSICAL REVIEW D. - 2015.

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The process e(+)e(-) - gamma chi(cJ) (J = 1, 2) is studied via initial state radiation using 980 fb(-1) of data at and around the Gamma(nS) (n = 1, 2, 3, 4, 5) resonances collected with the Belle detector at the KEKB asymmetricenergy e(+)e(-) collider. No significant signal is observed except from psi(2S) decays. Upper limits on the cross sections between root s = 3.80 and 5.56 GeV are determined at the 90% credibility level, which range from a few pb to a few tens of pb. We also set upper limits on the decay rate of the vector charmonium [psi(4040), psi(4160), and psi(4415)] and charmoniumlike [Y(4260), Y(4360), and Y(4660)] states to gamma chi(cJ).

Measurement of e(+)e(-) - pi(+)pi(-)psi(2S) via initial state radiation at Belle / Wang,XL / PHYSICAL REVIEW D. - 2015.

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We report measurement of the cross section of e(+)e(-) - pi(+)pi(-)psi(2S) between 4.0 and 5.5 GeV, based on an analysis of initial state radiation events in a 980 fb(-1) data sample recorded with the Belle detector. The properties of the Y(4360) and Y(4660) states are determined. Fitting the mass spectrum of pi(+)pi(-)psi(2S) with two coherent Breit-Wigner functions, we find two solutions with identical mass and width but different couplings to electron-positron pairs: M-Y(4360) = (4347 +/- 6 +/- 3) MeV/c(2), Gamma(Y(4360)) = (103 +/- 9 +/- 5) MeV, M-Y(4660) = (4652 +/- 10 +/- 8) MeV/c(2), Gamma(Y(4660)) = (68 +/- 11 +/- 1) MeV; and B[Y(4360) - pi(+)pi(-)psi(2S)] . Gamma(e+e-)(Y(4360)) = (10.9 +/- 0.6 +/- 0.7) eV and B[Y(4660) - pi(+)pi(-)psi(2S)] . Gamma(e+e-)(Y(4660)) = (8.1 +/- 1.1 +/- 0.5) eV for one solution; or B[Y(4360) - pi(+)pi(-)psi(2S)] . Gamma(e+e-)(Y(4360)) = (9.2 +/- 0.6 +/- 0.6) eV and B[Y(4660) - pi(+)pi(-)psi(2S)] . Gamma(e+e-)(Y(4660)) = (2.0 +/- 0.3 +/- 0.2) eV for the other. Here, the first errors are statistical and the second systematic. Evidence for a charged charmoniumlike structure at 4.05 GeV/c(2) is observed in the pi(+/-)psi(2S) intermediate state in the Y(4360) decays.

Measurement of electron-positron spectrum in high-energy cosmic rays in the PAMELA experiment / Adriani,O. / Journal of Physics: Conference Series. - 2015.

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At present the existing data on the cosmic ray electron energy spectra in the high energy range are fragmented, and the situation is exacerbated by their small number. In the satellite PAMELA experiment measurements at high energies are carried out by the calorimeter. The experimental data accumulated for more than 8 years of measurements, with the information of the calorimeter, the neutron detector and the scintillation counters made it possible to obtain the total spectrum of high-energy electrons and positrons in energy range 0.3-3 TeV. © Published under licence by IOP Publishing Ltd.

Measurement of electrons from semileptonic heavy-flavor hadron decays in pp collisions at s =2.76TeV / Abelev,B. / Physical Review D - Particles, Fields, Gravitation and Cosmology. - 2015.

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The pT-differential production cross section of electrons from semileptonic decays of heavy-flavor hadrons has been measured at midrapidity in proton-proton collisions at s=2.76TeV in the transverse momentum range 0.5<pT<12GeV/c with the ALICE detector at the LHC. The analysis was performed using minimum bias events and events triggered by the electromagnetic calorimeter. Predictions from perturbative QCD calculations agree with the data within the theoretical and experimental uncertainties.

Measurement of exclusive γγ→ℓsup+/supℓsup-/sup production in proton-proton collisions at √s=7 TeV with the ATLAS detector / Abbott,B. / Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 2015.

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This Letter reports a measurement of the exclusive γγ→ℓ+ℓ- (ℓ=e, μ) cross-section in proton-proton collisions at a centre-of-mass energy of 7 TeV by the ATLAS experiment at the LHC, based on an integrated luminosity of 4.6 fb-1. For the electron or muon pairs satisfying exclusive selection criteria, a fit to the dilepton acoplanarity distribution is used to extract the fiducial cross-sections. The cross-section in the electron channel is determined to be σγγ→e+e-excl.=0.428 ± 0.035 (stat.) ± 0.018 (syst.) pb for a phase-space region with invariant mass of the electron pairs greater than 24 GeV, in which both electrons have transverse momentum pT>12 GeV and pseudorapidity |η|<2.4. For muon pairs with invariant mass greater than 20 GeV, muon transverse momentum pT>10 GeV and pseudorapidity |η|<2.4, the cross-section is determined to be σγγ→μ+μ-excl.=0.628 ± 0.032 (stat.) ± 0.021 (syst.) pb. When proton absorptive effects due to the finite size of the proton are taken into account in the theory calculation, the measured cross-sections are found to be consistent with the theory prediction. © 2015 CERN for the benefit of the ATLAS Collaboration.

Measurement of four-jet differential cross sections in (Formula presented.) TeV proton-proton collisions using the ATLAS detector / Aad,G. / Journal of High Energy Physics. - 2015.

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Differential cross sections for the production of at least four jets have been measured in proton-proton collisions at (Formula presented.) TeV at the Large Hadron Collider using the ATLAS detector. Events are selected if the four anti-ktR = 0.4 jets with the largest transverse momentum (pT) within the rapidity range |y| 2.8 are well separated (ΔR4j min 0.65), all have pT 64 GeV, and include at least one jet with pT 100 GeV. The dataset corresponds to an integrated luminosity of 20.3 fb−1. The cross sections, corrected for detector effects, are compared to leading-order and next-to-leading-order calculations as a function of the jet momenta, invariant masses, minimum and maximum opening angles and other kinematic variables. © 2015, The Author(s).

Measurement of interaction between antiprotons / Adamczyk,L. / Nature. - 2015.

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One of the primary goals of nuclear physics is to understand the force between nucleons, which is a necessary step for understanding the structure of nuclei and how nuclei interact with each other. Rutherford discovered the atomic nucleus in 1911, and the large body of knowledge about the nuclear force that has since been acquired was derived from studies made on nucleons or nuclei. Although antinuclei up to antihelium-4 have been discovered and their masses measured, little is known directly about the nuclear force between antinucleons. Here, we study antiproton pair correlations among data collected by the STAR experiment at the Relativistic Heavy Ion Collider (RHIC), where gold ions are collided with a centre-of-mass energy of 200 gigaelectronvolts per nucleon pair. Antiprotons are abundantly produced in such collisions, thus making it feasible to study details of the antiproton-antiproton interaction. By applying a technique similar to Hanbury Brown and Twiss intensity interferometry, we show that the force between two antiprotons is attractive. In addition, we report two key parameters that characterize the corresponding strong interaction: the scattering length and the effective range of the interaction. Our measured parameters are consistent within errors with the corresponding values for proton-proton interactions. Our results provide direct information on the interaction between two antiprotons, one of the simplest systems of antinucleons, and so are fundamental to understanding the structure of more-complex antinuclei and their properties. © 2015 Macmillan Publishers Limited. All rights reserved.

Measurement of jet quenching with semi-inclusive hadron-jet distributions in central Pb-Pb collisions at vsNN = 2.76 TeV / TheATLASCollaboration / Journal of High Energy Physics. - 2015.

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We report the measurement of a new observable of jet quenching in central Pb-Pb collisions at vsNN = 2.76 TeV, based on the semi-inclusive rate of charged jets recoiling from a high transverse momentum (high-pinfT/inf) charged hadron trigger. Jets are measured using collinear-safe jet reconstruction with infrared cutoff for jet constituents of 0.15 GeV, for jet resolution parameters R = 0.2, 0.4 and 0.5. Underlying event background is corrected at the event-ensemble level, without imposing bias on the jet population. Recoil jet spectra are reported in the range 20 pinfT,jet/infch 100 GeV. Reference distributions for pp collisions at vs

Measurement of jet suppression in central Pb-Pb collisions at sNN=2.76 TeV / Adamová,D. / Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 2015.

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The transverse momentum (pinfT/inf) spectrum and nuclear modification factor (RinfAA/inf) of reconstructed jets in 0-10% and 10-30% central Pb-Pb collisions at sNN=2.76 TeV were measured. Jets were reconstructed using the anti-kinfT/inf jet algorithm with a resolution parameter of R=0.2 from charged and neutral particles, utilizing the ALICE tracking detectors and Electromagnetic Calorimeter (EMCal). The jet pinfT/inf spectra are reported in the pseudorapidity interval of |ηinfjet/inf|<0.5 for 40<pinfT,jet/inf<120 GeV/c in 0-10% and for 30<pinfT,jet/inf<100 GeV/c in 10-30% collisions. Reconstructed jets were required to contain a leading charged particle with pinfT/inf>5 GeV/c to suppress jets constructed from the combinatorial background in Pb-Pb collisions. The leading charged particle requirement applied to jet spectra both in pp and Pb-Pb collisions had a negligible effect on the RinfAA/inf. The nuclear modification factor RinfAA/inf was found to be 0.28±0.04 in 0-10% and 0.35±0.04 in 10-30% collisions, independent of pinfT,jet/inf within the uncertainties of the measurement. The observed suppression is in fair agreement with expectations from two model calculations with different approaches to jet quenching. © 2015.

Measurement of Linear Energy Transfer Spectra of High-LET Space Radiation Inside the International Space Station Modules (2013-2014) / Shurshakov,V.A. / Physics Procedia. - 2015.

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The field of space radiation in low-Earth orbit is extremely complicated due to many reasons. It is formed mainly of galactic cosmic rays (GCR), solar particles and trapped particles in the south Atlantic anomaly region. In addition radiation field is affected by shielding and scattering of incident primary particles by surrounding material. The contribution of short - range particles produced in the nuclear interactions in the shielding and contents of the spacecraft to the total radiation field is comparable to the primary component at high values of dE/dx. Preliminary linear energy transfer (LET) spectra of high-LET space radiation were measured in different compartments of the Russian segment of International Space Station (ISS) by means of plastic nuclear track detectors (PNTD) CR-39 TASTRACK. Measurements were carried out during ISS-37/38/39 expeditions in MATROSHKA-R space experiment. The comparison of experimental spectra with simulated one was made in order of data verification. © 2015 The Authors.

Measurement of pion, kaon and proton production in proton–proton collisions at √s = 7 TeV / Adam,J. / European Physical Journal C. - 2015.

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The measurement of primary $$$$supπ±/sup, $$K$$supK±/sup, $$p$$p and $$p$$p¯ production at mid-rapidity ($$|y| <$$|y|< 0.5) in proton–proton collisions at $$s$$s$$=$$= 7 TeV performed with a large ion collider experiment at the large hadron collider (LHC) is reported. Particle identification is performed using the specific ionisation energy-loss and time-of-flight information, the ring-imaging Cherenkov technique and the kink-topology identification of weak decays of charged kaons. Transverse momentum spectra are measured from 0.1 up to 3 GeV/$$c$$c for pions, from 0.2 up to 6 GeV/$$c$$c for kaons and from 0.3 up to 6 GeV/$$c$$c for protons. The measured spectra and particle ratios are compared with quantum chromodynamics-inspired models, tuned to reproduce also the earlier measurements performed at the LHC. Furthermore, the integrated particle yields and ratios as well as the average transverse momenta are compared with results at lower collision energies. © 2015, CERN for the benefit of the ALICE collaboration.

Measurement of Spin Correlation in Top-Antitop Quark Events and Search for Top Squark Pair Production in pp Collisions at root s=8 TeV Using the ATLAS Detector / Aad,G / PHYSICAL REVIEW LETTERS. - 2015.

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A measurement of spin correlation in t (t) over bar production is presented using data collected with the ATLAS detector at the Large Hadron Collider in proton-proton collisions at a center-of-mass energy of 8 TeV, corresponding to an integrated luminosity of 20.3 fb(-1). The correlation between the top and antitop quark spins is extracted from dilepton t (t) over bar events by using the difference in the azimuthal angle between the two charged leptons in the laboratory frame. In the helicity basis the measured degree of correlation corresponds to A(helicity) = 0.38 +/- 0.04, in agreement with the standard model prediction. A search is performed for pair production of top squarks with masses close to the top quark mass decaying to predominantly right-handed top quarks and a light neutralino, the lightest supersymmetric particle. Top squarks with masses between the top quark mass and 191 GeV are excluded at the 95% confidence level.

Measurement of the B ¯ →xsγ branching fraction with a sum of exclusive decays MEASUREMENT of THE. T. SAITO et al. / Saito,T. / Physical Review D - Particles, Fields, Gravitation and Cosmology. - 2015.

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We use 772×106 BB¯ meson pairs collected at the ?(4S) resonance with the Belle detector to measure the branching fraction for B¯→Xsγ. Our measurement uses a sum-of-exclusives approach in which 38 of the hadronic final states with strangeness equal to +1, denoted by Xs, are reconstructed. The inclusive branching fraction for MXs<2.8GeV/c2, which corresponds to a minimum photon energy of 1.9 GeV, is measured to be B(B¯→Xsγ)=(3.51±0.17±0.33)×10-4, where the first uncertainty is statistical and the second is systematic.

Measurement of the branching fraction of B+ - tau(+)nu(tau) decays with the semileptonic tagging method / Kronenbitter,B / PHYSICAL REVIEW D. - 2015.

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We report a measurement of the branching fraction of B+ - tau(+) nu(tau) decays using a data sample of 772 x 10(6) B (B) over bar pairs, collected at the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider. We reconstruct the accompanying B meson in a semileptonic decay and detect the recoiling B candidate in the decay channel B+ - tau(+) nu(tau). We obtain a branching fraction of B(B+ - tau(+) nu(tau)) = [1.25 +/- 0.28(stat.) +/- 0.27(syst.)] x 10-(4). This result is in good agreement with previous measurements and the expectation from the calculation based on the Standard Model.

Measurement of the branching ratio Gamma(Lambda(0)(b) - Psi(2S)Lambda(0))/ Gamma(Lambda(0.)(b) - J/Psi Lambda(0)) with the ATLAS detector / Aad,G / PHYSICS LETTERS B. - 2015.

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An observation of the Lambda(0)(b) - Psi (2S) Lambda(0) decay and a comparison of its branching fraction with that of the Lambda(0)(b) - Psi (2S) Lambda(0) decay has been made with the ATLAS detector in proton-proton collisions at root s = 8 TeVat the LHC using an integrated luminosity of 20.6fb(-1). The J/Psi and Psi(2S) mesons are reconstructed in their decays to a muon pair, while the Lambda(0) - p pi(-) decay is exploited for the Lambda(0) 0baryon reconstruction. The Lambda(0)(b) baryons are reconstructed with transverse momentum p(T) 10 GeVand pseudorapidity vertical bar eta vertical bar 2.1. The measured branching ratio of the Lambda(0)(b) - Psi (2S) Lambda(0) and Lambda(0)(b) - Psi (2S) Lambda(0) decays is Gamma(Lambda(0)(b) - Psi (2S) Lambda(0)) / Gamma(Lambda(0)(b) - Psi (2S) Lambda(0)) = 0.501 +/- 0.033(stat) +/- 0.019(syst), lower than the expectation from the covariant quark model. (C) 2015 CERN for the benefit of the ATLAS Collaboration. Published by Elsevier B.V.

Measurement of the branching ratio of B ¯ →d (∗)τ- ν ¯ τ relative to B ¯ →d (∗) - ν ¯ decays with hadronic tagging at Belle MEASUREMENT of the BRANCHING RATIO of … M. HUSCHLE et al. / Huschle,M. / Physical Review D - Particles, Fields, Gravitation and Cosmology. - 2015.

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We report a measurement of the branching fraction ratios R(D(∗)) of B¯→D(∗)τ-ν¯τ relative to B¯→D(∗) -ν¯ (where =e or μ) using the full Belle data sample of 772×106BB¯ pairs collected at the (4S) resonance with the Belle detector at the KEKB asymmetric-energy e+e- collider. The measured values are R(D)=0.375±0.064(stat)±0.026(syst) and R(D∗)=0.293±0.038(stat)±0.015(syst). The analysis uses hadronic reconstruction of the tag-side B meson and purely leptonic τ decays. The results are consistent with earlier measurements and do not show a significant deviation from the standard model prediction. © 2015 American Physical Society. © 2015 American Physical Society.

Measurement of the charge asymmetry in dileptonic decays of top quark pairs in pp collisions at root s=7 TeV using the ATLAS detector / Aad,G / JOURNAL OF HIGH ENERGY PHYSICS. - 2015

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A measurement of the top-antitop (t (t) over bar) charge asymmetry is presented using data corresponding to an integrated luminosity of 4.6 fb(-1) of LHC pp collisions at a centre-of-mass energy of 7 TeV collected by the ATLAS detector. Events with two charged leptons, at least two jets and large missing transverse momentum are selected. Two observables are studied: A(C)(ll) based on the identified charged leptons, and A(C)(t (t) over bar), based on the reconstructed t (t) over bar final state. The asymmetries are measured to be A(C)(ll) =0.024 +/- 0.015 (stat.) +/- 0.009 (syst.), A(C)(t (t) over bar) = 0.021 +/- 0.025 (stat.) +/- 0.017 (syst.). The measured values are in agreement with the Standard Model predictions.

Measurement of the correlation between flow harmonics of different order in lead-lead collisions at s NN =2.76 TeV with the ATLAS detector / Aad,G. / Physical Review C - Nuclear Physics. - 2015.

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Correlations between the elliptic or triangular flow coefficients vm (m=2 or 3) and other flow harmonics vn (n=2 to 5) are measured using sNN=2.76 TeV Pb+Pb collision data collected in 2010 by the ATLAS experiment at the LHC, corresponding to an integrated luminosity of 7 μb-1. The vm-vn correlations are measured in midrapidity as a function of centrality, and, for events within the same centrality interval, as a function of event ellipticity or triangularity defined in a forward rapidity region. For events within the same centrality interval, v3 is found to be anticorrelated with v2 and this anticorrelation is consistent with similar anticorrelations between the corresponding eccentricities, ε2 and ε3. However, it is observed that v4 increases strongly with v2, and v5 increases strongly with both v2 and v3. The trend and strength of the vm-vn correlations for n=4 and 5 are found to disagree with εm-εn correlations predicted by initial-geometry models. Instead, these correlations are found to be consistent with the combined effects of a linear contribution to vn and a nonlinear term that is a function of v22 or of v2v3, as predicted by hydrodynamic models. A simple two-component fit is used to separate these two contributions. The extracted linear and nonlinear contributions to v4 and v5 are found to be consistent with previously measured event-plane correlations. © 2015 CERN. ©2015 CERN, for the ATLAS Collaboration. Published by the American Physical Society under the terms of the Creative Commons Attribution 3.0 License. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.

Measurement of the Direct CP Asymmetry in over-bar & RARR; gamma; Decays with a Lepton Tag / Pesantez,L / PHYSICAL REVIEW LETTERS. - 2015.

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We report the measurement of the direct CP asymmetry in the radiative (B) over bar - Xs+d gamma decay using a data sample of (772 +/- 11) x 10(6) B (B) over bar pairs collected at the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider. The CP asymmetry is measured as a function of the photon energy threshold. For E-gamma* = 2.1 GeV, where E-gamma* is the photon energy in the center-of-mass frame, we obtain A(CP) ((B) over bar - Xs+d gamma) = (2.2 +/- 3.9 +/- 0.9)%, consistent with the standard model prediction.

Measurement of the electron neutrino charged-current interaction rate on water with the T2K ND280 pi(0) detector / Abe,K. / PHYSICAL REVIEW D. - 2015.

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This paper presents a measurement of the charged current interaction rate of the electron neutrino beam component of the beam above 1.5 GeV using the large fiducial mass of the T2K pi(0) detector. The predominant portion of the v(e) flux (similar to 85%) at these energies comes from kaon decays. The measured ratio of the observed beam interaction rate to the predicted rate in the detector with water targets filled is 0.89 +/- 0.08(stat) +/- 0.11(sys), and with the water targets emptied is 0.90 +/- 0.09(stat) +/- 0.13 (sys). The ratio obtained for the interactions on water only from an event subtraction method is 0.87 +/- 0.33(stat) +/- 0.21(sys). This is the first measurement of the interaction rate of electron neutrinos on water, which is particularly of interest to experiments with water Cherenkov detectors.

Measurement of the forward-backward asymmetry of electron and muon pair-production in pp collisions at (Formula Presented.) = 7 TeV with the ATLAS detector / TheATLAScollaboration / Journal of High Energy Physics. - 2015.

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This paper presents measurements from the ATLAS experiment of the forward-backward asymmetry in the reaction pp → Z/γsup*/sup → lsup+/suplsup−/sup, with l being electrons or muons, and the extraction of the effective weak mixing angle. The results are based on the full set of data collected in 2011 in pp collisions at the LHC at (Formula presented.), corresponding to an integrated luminosity of 4.8 fbsup−1/sup. The measured asymmetry values are found to be in agreement with the corresponding Standard Model predictions. The combination of the muon and electron channels yields a value of the effective weak mixing angle of sinsup2/supθinfeff/inf; suplept/sup = 0.2308 ± 0.0005(stat.) ± 0.0006(syst.) ± 0.0009(PDF), where the first uncertainty corresponds to data statistics, the second to systematic effects and the third to knowledge of the parton density functions. This result agrees with the current world average from the Particle Data Group fit. © 2015, The Author(s).

Measurement of the inclusive jet cross-section in proton-proton collisions at root s = 7 TeV using 4.5 fb(-1) of data with the ATLAS detector (vol 2, 153, 2015) / Aad,G / JOURNAL OF HIGH ENERGY PHYSICS. - 2015

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It was found that the non-perturbative corrections calculated using Pythia with the Perugia 2011 tune did not include the effect of the underlying event. The affected correction factors were recomputed using the Pythia 6.427 generator. These corrections are applied as baseline to the NLO pQCD calculations and thus the central values of the theoretical predictions have changed by a few percent with the new corrections. This has a minor impact on the agreement between the data and the theoretical predictions. Figures 2 and 6 to 13, and all the tables have been updated with the new values. A few sentences in the discussion in sections 5.2 and 9 were altered or removed.

Measurement of the inclusive jet cross-section in proton-proton collisions at root s=7 TeV using 4.5 fb(-1) of data with the ATLAS detector / Aad,G / JOURNAL OF HIGH ENERGY PHYSICS. - 2015

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The inclusive jet cross-section is measured in proton-proton collisions at a centre-of-mass energy of 7 TeV using a data set corresponding to an integrated luminosity of 4.5 fb(-1) collected with the ATLAS detector at the Large Hadron Collider in 2011. Jets are identified using the anti-k(t) algorithm with radius parameter values of 0.4 and 0.6. The double-differential cross-sections are presented as a function of the jet transverse momentum and the jet rapidity, covering jet transverse momenta from 100 GeV to 2 TeV. Next-to-leading-order QCD calculations corrected for non-perturbative effects and electroweak effects, as well as Monte Carlo simulations with next-to-leading-order matrix elements interfaced to parton showering, are compared to the measured cross-sections. A quantitative comparison of the measured cross-sections to the QCD calculations using several sets of parton distribution functions is performed.

Measurement of the large-scale anisotropy of cosmic rays in the PAMELA experiment / Adriani,O. / JETP Letters. - 2015.

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Large-scale anisotropy or so-called sidereal-diurnal wave has been detected in the PAMELA satellite experiment in the time interval of 2006–2014. The magnitude of anisotropy has been measured simultaneously for the Southern and Northern Hemispheres in the equatorial coordinate system. The results confirm the data of ground-based experiments. © 2015, Pleiades Publishing, Inc.

Measurement of the nu(mu) charged current quasielastic cross section on carbon with the T2K on-axis neutrino beam / Abe,K / PHYSICAL REVIEW D. - 2015.

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We report a measurement of the nu(mu) charged current quasielastic cross-sections on carbon in the T2K on-axis neutrino beam. The measured charged current quasielastic cross-sections on carbon at mean neutrino energies of 1.94 GeV and 0.93 GeV are (11.95 +/- 0.19(stat)(-1.47)(+1.82)(syst)) x 10(-39) cm(2)/neutron, and (10.64 +/- 0.37(stat)(-1.65)(+2.03)(syst)) x 10(-39) cm(2)/neutron, respectively. These results agree well with the predictions of neutrino interaction models. In addition, we investigated the effects of the nuclear model and the multi-nucleon interaction.

Measurement of the production and lepton charge asymmetry of W bosons in Pb+Pb collisions at vsNN=2.76TeV with the ATLAS detector / ATLASCollaboration / European Physical Journal C. - 2015.

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A measurement of (Formula presented.)boson production in lead-lead collisions at (Formula presented.)(Formula presented.) is presented. It is based on the analysis of data collected with the ATLAS detector at the LHC in 2011 corresponding to an integrated luminosity of 0.14 (Formula presented.)(Formula presented.) and 0.15(Formula presented.)(Formula presented.)in the muon and electron decay channels, respectively. The differential production yields and lepton charge asymmetry are each measured as a function of the average number of participating nucleons (Formula presented.)(Formula presented.) and absolute pseudorapidity of the charged lepton. The results are compared to predictions based on next-to-leading-order QCD calculations. These measurements are, in principle, sensitive to possible nuclear modifications to the parton distribution functions and also provide information on scaling of(Formula presented.)(Formula presented.)boson production in multi-nucleon systems.

Measurement of the production of neighbouring jets in lead-lead collisions at √sNN=2.76 TeV with the ATLAS detector / Aad,G. / Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 2015.

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This Letter presents measurements of correlated production of nearby jets in Pb+Pb collisions at √sNN=2.76 TeV using the ATLAS detector at the Large Hadron Collider. The measurement was performed using 0.14 nbsup-1/sup of data recorded in 2011. The production of correlated jet pairs was quantified using the rate, RδR, of "neighbouring" jets that accompany "test" jets within a given range of angular distance, δR, in the pseudorapidity-azimuthal angle plane. The jets were measured in the ATLAS calorimeter and were reconstructed using the anti-kt algorithm with radius parameters d=0.2, 0.3, and 0.4. RδR was measured in different Pb+Pb collision centrality bins, characterized by the total transverse energy measured in the forward calorimeters. A centrality dependence of RδR is observed for all three jet radii with RδR found to be lower in central collisions than in peripheral collisions. The ratios formed by the RδR values in different centrality bins and the values in the 40-80% centrality bin are presented. © 2015.

Measurement of the t(t)over-bar production cross-section as a function of jet multiplicity and jet transverse momentum in 7 TeV proton-proton collisions with the ATLAS detector / Aad,G / JOURNAL OF HIGH ENERGY PHYSICS. - 2015.

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The t (t) over bar production cross-section dependence on jet multiplicity and jet transverse momentum is reported for proton-proton collisions at a centre-of-mass energy of 7 TeV in the single-lepton channel. The data were collected with the ATLAS detector at the CERN Large Hadron Collider and comprise the full 2011 data sample corresponding to an integrated luminosity of 4.6 fb(-1). Differential cross-sections are presented as a function of the jet multiplicity for up to eight jets using jet transverse momentum thresholds of 25, 40, 60, and 80 GeV, and as a function of jet transverse momentum up to the fifth jet. The results are shown after background subtraction and corrections for all known detector effects, within a kinematic range closely matched to the experimental acceptance. Several QCD-based Monte Carlo models are compared with the results. Sensitivity to the parton shower modelling is found at the higher jet multiplicities, at high transverse momentum of the leading jet and in the transverse momentum spectrum of the fifth leading jet. The MC@NLO+HERWIG MC is found to predict too few events at higher jet multiplicities.

Measurement of the t(t)over-barW and t(t)over-barZ production cross sections in pp collisions at root s=8 TeV with the ATLAS detector / Aad,G / JOURNAL OF HIGH ENERGY PHYSICS. - 2015

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The production cross sections of top-quark pairs in association with massive vector bosons have been measured using data from pp collisions at root s = 8 TeV. The dataset corresponds to an integrated luminosity of 20.3 fb(-1) collected by the ATLAS detector in 2012 at the LHC. Final states with two, three or four leptons are considered. A fit to the data considering the t (t) over barW and t (t) over barZ processes simultaneously yields a significance of 5.0 sigma (4.2 sigma) over the background-only hypothesis for t (t) over barW (t (t) over barZ) production. The measured cross sections are sigma(t (t) over barW) = 369(-91)(+100) fb and sigma(t (t) over barZ) = 176(-52)(+58) fb. The background-only hypothesis with neither t (t) over barW nor t (t) over barZ production is excluded at 7.1 sigma. All measurements are consistent with next-to-leading-order calculations for the t (t) over barW and t (t) over barZ processes.

Measurement of the top pair production cross section in 8 TeV proton-proton collisions using kinematic information in the lepton plus jets final state with ATLAS / Aad,G / PHYSICAL REVIEW D. - 2015.

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A measurement is presented of the (tt) over bar inclusive production cross section in pp collisions at a center-ofmass energy of pffisffiffi root s = 8 TeV using data collected by the ATLAS detector at the CERN Large Hadron Collider. The measurement was performed in the lepton + jets final state using a data set corresponding to an integrated luminosity of 20.3 fb(-1). The cross section was obtained using a likelihood discriminant fit and b-jet identification was used to improve the signal-to-background ratio. The inclusive (tt) over bar production cross section was measured to be 260 +/- 1(stat)(-23)(+22)(stat) +/- 8(lumi) +/- 4(beam) pb assuming a top-quark mass of 172.5 GeV, in good agreement with the theoretical prediction of 253(-15)(+13) pb. The (tt) over bar - (e, mu) + jets production cross section in the fiducial region determined by the detector acceptance is also reported.

Measurement of the top-quark mass in the fully hadronic decay channel from ATLAS data at (Formula presented.) / ATLASCollaboration / European Physical Journal C. - 2015.

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The mass of the top quark is measured in a data set corresponding to 4.6 (Formula presented.) of proton–proton collisions with centre-of-mass energy (Formula presented.) TeV collected by the ATLAS detector at the LHC. Events consistent with hadronic decays of top–antitop quark pairs with at least six jets in the final state are selected. The substantial background from multijet production is modelled with data-driven methods that utilise the number of identified $$b$$b-quark jets and the transverse momentum of the sixth leading jet, which have minimal correlation. The top-quark mass is obtained from template fits to the ratio of three-jet to dijet mass. The three-jet mass is calculated from the three jets produced in a top-quark decay. Using these three jets the dijet mass is obtained from the two jets produced in the W boson decay. The top-quark mass obtained from this fit is thus less sensitive to the uncertainty in the energy measurement of the jets. A binned likelihood fit yields a top-quark mass of (Formula presented.). © 2015, CERN for the benefit of the ATLAS Collaboration.

Measurement of the total spectrum of electrons and positrons in the energy range of 300-1500 GeV in the PAMELA experiment with the aid of a sampling calorimeter and a neutron detector / Karelin,AV / PHYSICS OF ATOMIC NUCLEI. - 2015.

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A method based on the use of a sampling calorimeter was developed for measuring the total energy spectrum of electrons and positrons from high-energy cosmic rays in the PAMELA satellite-borne experiment. This made it possible to extend the range of energies accessible to measurements by the magnetic system of the PAMELA spectrometer. Themethod involves a procedure for selecting electrons on the basis of features of a secondary-particle shower in the calorimeter. The results obtained by measuring the total spectrum of cosmic-ray electrons and positrons in the energy range of 300-1500 GeV by the method in question are presented on the basis of data accumulated over a period spanning 2006 and 2013.

Measurement of the transverse polarization of Λ and Λ ¯ hyperons produced in proton-proton collisions at s =7TeV using the ATLAS detector / Aad,G. / Physical Review D - Particles, Fields, Gravitation and Cosmology. - 2015.

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The transverse polarization of Λ and Λ¯ hyperons produced in proton-proton collisions at a center-of-mass energy of 7 TeV is measured. The analysis uses 760μb-1 of minimum bias data collected by the ATLAS detector at the LHC in the year 2010. The measured transverse polarization averaged over Feynman xF from 5×10-5 to 0.01 and transverse momentum pT from 0.8 to 15 GeV is -0.010±0.005(stat)±0.004(syst) for Λ and 0.002±0.006(stat)±0.004(syst) for Λ¯. It is also measured as a function of xF and pT, but no significant dependence on these variables is observed. Prior to this measurement, the polarization was measured at fixed-target experiments with center-of-mass energies up to about 40 GeV. The ATLAS results are compatible with the extrapolation of a fit from previous measurements to the xF range covered by this measurement.

Measurement of the underlying event activity using charged-particle jets in proton-proton collisions at √s=2.76 TeV / TheCMScollaboration / Journal of High Energy Physics. - 2015.

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A measurement of the underlying event (UE) activity in proton-proton collisions is performed using events with charged-particle jets produced in the central pseudorapidity region (|ηsupjet/sup| < 2) and with transverse momentum 1 ≤ pinfT/inf supjet/sup < 100 GeV. The analysis uses a data sample collected at a centre-of-mass energy of 2.76 TeV with the CMS experiment at the LHC. The UE activity is measured as a function of pinfT/inf supjet/sup in terms of the average multiplicity and scalar sum of transverse momenta (pinfT/inf) of charged particles, with |η| < 2 and pinfT/inf > 0.5 GeV, in the azimuthal region transverse to the highest pinfT/inf jet direction. By further dividing the transverse region into two regions of smaller and larger activity, various components of the UE activity are separated. The measurements are compared to previous results at 0.9 and 7 TeV, and to predictions of several Monte Carlo event generators, providing constraints on the modelling of the UE dynamics.[Figure not available: see fulltext.] © 2015, The Author(s).

Measurement of the WW plus WZ cross section and limits on anomalous triple gauge couplings using final states with one lepton, missing transverse momentum, and two jets with the ATLAS detector at root s=7 TeV / Aad,G / JOURNAL OF HIGH ENERGY PHYSICS. - 2015

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The production of a W boson decaying to ev or mu v in association with a W or Z boson decaying to two jets is studied using 4.6 fb(-1) of proton-proton collision data at root s = 7 TeV recorded with the ATLAS detector at the LHC. The combined WW + WZ cross section is measured with a significance of 3.4 sigma and is found to be 68 +/- 7 (stat.) +/- 19 (syst.) pb, in agreement with the Standard Model expectation of 61.1 +/- 2.2 pb. The distribution of the transverse momentum of the dijet system is used to set limits on anomalous contributions to the triple gauge coupling vertices and on parameters of an effective-field-theory model.

Measurement of the Z boson differential cross section in transverse momentum and rapidity in proton-proton collisions at 8 TeV / Khachatryan,V. / Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 2015.

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We present a measurement of the Z boson differential cross section in rapidity and transverse momentum using a data sample of pp collision events at a centre-of-mass energy s=8 TeV, corresponding to an integrated luminosity of 19.7 fb-1. The Z boson is identified via its decay to a pair of muons. The measurement provides a precision test of quantum chromodynamics over a large region of phase space. In addition, due to the small experimental uncertainties in the measurement the data has the potential to constrain the gluon parton distribution function in the kinematic regime important for Higgs boson production via gluon fusion. The results agree with the next-to-next-to-leading-order predictions computed with the fewz program. The results are also compared to the commonly used leading-order MadGraph and next-to-leading-order powheg generators. © 2015 CERN for the benefit of the CMS Collaboration.

Measurement of the Zγ production cross section in pp collisions at 8 TeV and search for anomalous triple gauge boson couplings / TheCMScollaboration / Journal of High Energy Physics. - 2015.

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Abstract: The cross section for the production of Zγ in proton-proton collisions at 8 TeV is measured based on data collected by the CMS experiment at the LHC corresponding to an integrated luminosity of 19.5 fbsup−1/sup. Events with an oppositely-charged pair of muons or electrons together with an isolated photon are selected. The differential cross section as a function of the photon transverse momentum is measured inclusively and exclusively, where the exclusive selection applies a veto on central jets. The observed cross sections are compatible with the expectations of next-to-next-to-leading-order quantum chromodynamics. Limits on anomalous triple gauge couplings of ZZγ and Zγγ are set that improve on previous experimental results obtained with the charged lepton decay modes of the Z boson.[Figure not available: see fulltext.] © 2015, The Author(s).

Measurement of the νμ charged-current quasielastic cross section on carbon with the ND280 detector at T2K / Abe,K. / Physical Review D - Particles, Fields, Gravitation and Cosmology. - 2015.

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This paper reports a measurement by the T2K experiment of the νμ charged current quasielastic (CCQE) cross section on a carbon target with the off-axis detector based on the observed distribution of muon momentum (pμ) and angle with respect to the incident neutrino beam (θμ). The flux-integrated CCQE cross section was measured to be «σ © 2015 authors. Published by the American Physical Society.