Investigation of hadron interactions at ultra-high energies based on the study of hadrons characteristics in EAS cores

Abstract

This work is devoted to the study of interactions of primary cosmic radiation particles, which can currently be conducted mainly indirectly, by comparing a limited set of traditional characteristics of extensive atmospheric showers with simulation results. The presented work uses the high-altitude ionisation calorimeter ‘Adron-55’, which has the ability to register the most informative high-energy hadronic component in the stems of the EAS, which provides a deeper level of analysis. To increase the spatial and longitudinal resolution of the Adron-55 installation, it has been upgraded by installing and connecting a lower, ninth row of ionization chambers. This additional measuring layer allows the longitudinal structure of the shower to be refined and the accuracy of the reconstruction of the energy distribution of hadrons at large atmospheric depths to be improved. Based on the accumulated experimental data, a physical programme has been implemented to study the longitudinal, transverse and azimuthal characteristics of WACR showers. Such a comprehensive analysis of the spatial parameters of the cascade provides new information about the mechanisms of development of the hadron component and the interactions of ultra-high-energy UCE particles in the Earth's atmosphere.