Enhancement of the Yakutsk array by atmospheric Cherenkov telescopes to study cosmic rays above 10¹⁵ eV

Abstract

The aim of the Yakutsk array enhancement project is to create an instrument to study the highest-energy galactic cosmic rays (CRs) – their sources, energy spectrum, and mass composition. Additionally, there will be unique capabilities for investigations in the transition region between galactic and extragalactic components of CRs. <br><br> Using the well-developed imaging atmospheric Cherenkov telescope technique adapted to the energy region <i>E</i>>10¹⁵ eV, we plan to measure the longitudinal structure parameters of the shower, e.g. angular and temporal distributions of the Cherenkov signal related to <i>X</i>_max and the mass composition of CRs. <br><br> The main advantages of the Yakutsk array, such as its multi-component measurements of extensive air showers, and model-independent CR energy estimation based on Cherenkov light measurements, will be inherited by the instrument to be created

Temporal signatures of the Cherenkov light induced by extensive air showers of cosmic rays detected with the Yakutsk array

“…The key objective in this context is improvement of synchronization of the array detectors in order to refine the core location accuracy and measurement of time differences between signals in detectors. The Yakutsk array modernization program 8,18 in progress now includes the best part of the improvements needed. Particularly, a target synchronization accuracy of detectors is δt = 5 ns to be implemented with Gigabit Ethernet via optical fibers.…”

Yakutsk array cherenkov telescope prototype

“…Combining it with EAS axis coordinates determined by the scintillation counters of the array, we found the height of the maximum to be h m ≤ 1300 m, corresponding to x Cher m ≥ 850 g/cm 2 . In this particular shower, the lower limit to the depth is the result of the maximum of light intensity located at the edge of the telescope aperture.…”

“…[1] A crucial role in this program should play a cherenkov telescope array that observe light emitted by the extensive air showers for measuring angular and temporal signal structures associated with the cascade curve in showers with energies above E = 10 15 eV. [2] Our intention to develop a cherenkov telescope functioning as a differential detector of EAS was motivated by the possibility to measure the depth of the cascade maximum and/or the shower age via angular and temporal distributions of the cherenkov signal [3]. Combining X max and the shower age with other characteristics measured with surface detectors of the EAS array, e.g.…”

The study of cosmic rays with a wide-angle Cherenkov telescope

“…The scheme of ray tracing is illustrated in (Fig. 2) , where the spherical aberration of the point source image is seen on the PMT photocathode surface [2] [3].…”