Search for ultra-high energy photons by complex data of the Yakutsk array

Abstract

Complex analysis of the Yakutsk array data in order to find air showers produced by photons with energy ≥1018 eV is carried out. On the basis of simulations and experimental data, selection criteria are formed and air showers with characteristics close to those criteria are selected. Using the data an upper limit of the integral photon flux in cosmic radiation of ultra-high energies is obtained.