Search for structures in the distribution of particles from the central area of wide atmospheric showers conducted on the Adron-55 installation

Abstract

The ionization calorimeter “Adron-55”, located at an altitude of 3340 meters above sea level, is part
of the unified registration system for the shower installation of the Tian-Shan high-mountain station. The
“Hadron-55” installation is a 2-tier ionization calorimeter consisting of a shower system, a gamma block
and a hadron block located under it with a vertical air gap of 2.2 meters. The calorimeter consists of 6
layers of ionization chambers with 144 chambers in each layer and a spatial resolution of the WAS
structure equal to 11 cm. The total area of the calorimeter is 55 square meters with an absorber thickness
of 1150 g / cm². The calorimeter also contains helium counters for recording the neutron component. The
central shower calorimeter system contains 30 scintillation detectors with an area of 400 m² and 8
peripheral Sc-detectors at a distance of up to 100 m. The total area of the entire recording system is ~
30000 m². Over 4 years of operation, more than 120,000 events with energies above 10¹⁵ eV have been
recorded. Currently, the processing and analysis of the data being obtained are performed.