Scientists are closer to understanding the nature of ultra-high-energy cosmic rays

For decades, scientists all over the world have pondered the conundrum of ultra-high-energy gamma rays.  In view of new developments, scientists today are hoping to be able to research the processes of birth and propagation of ultra-high-energy gamma rays, which might eventually lead them to unveiling the mysterious dark matter particles which have so far evaded physicists around the world.

Tunka Advanced Instrument for cosmic ray physics and Gamma Astronomy (TAIGA), an international scientific collaboration, is launching one of the world’s largest and most sensitive high-energy gamma-ray observatories.  For the first time, the researchers will have a chance to study gamma radiation and ultra-high energy cosmic rays - reported the science team in its article: “Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment(link is external)”.


At the two TAIGA observatory facilities, scientists from Moscow State University (MSU), National Research Nuclear University MEPhI (MEPhI), Irkutsk State University Applied Physics Institute and other leading Russian and German universities are preparing for new series of experiments.  With the help of an array of distributed detector stations TAIGA-HiSCORE and new telescopes TAIGA –IACT, the researchers are expecting to record the “image” of Cherenkov radiation from a cascade of ionized particles produced via interaction of high-energy gamma-quanta with atmospheric atoms.

TAIGA complex is situated in Tunka Valley, 50 km off the southern tip of Lake Baikal. The experiments are carried out in autumn, winter and spring, as the detectors collect their data on moonless nights, and summer nights in Russia are too short. 

The complex employs new hybrid design technology that detects extensive air showers (EAS), generated by gamma quanta. In addition to Cherenkov radiation, it can also detect all the main EAS components produced in the atmosphere when a primary cosmic ray enters it.

“Today, the complex is at the deployment stage, the number of detectors at the facilities and the area of their registration is increasing. Methods of recording, processing and analyzing data are being developed, and their accuracy is continuously enhanced as planned. TAIGA is gradually going through all the necessary stages of any large-scale experimental complex,” commented Igor Yashin, a professor at the MEPhI Institute of Nuclear Physics and Engineering.

TAIGA plans for the near future include assembling and launching the third Cherenkov telescope; as well as raising the total number of TAIGA-HiSCORE detector stations up to120 units per one square kilometer. 

In winter, gamma-radiation flux measurements from known gamma sources, such as a pulsar in the Cancer Constellation, are scheduled to take place.

The MEPhI group is tasked with testing photomultipliers and related electronics for installing TAIGA-HiSCORE, developing and ensuring the operability of Cherenkov telescope camera electronics, performing the observatory duties at the TAIGA observatory, and other responsibilities. 

The origin of cosmic rays (high-energy protons and atomic nuclei) is one of the most vital mysteries of modern science. Upon solving it, humanity may come closer to creating new sources of super-high energy, such as space-based particle accelerators, that could provide billions of times more acceleration energy than the most powerful particle accelerator on Earth - the Large Hadron Collider.