Gamma-Astronomical Investigations at the Tien Shan High-Altitude Scientific Station of the Lebedev Physical Institute Based on Selection of Extensive Air Showers without Hadronic and Muonic Content.

We discuss the first results of and prospects for performing gamma-astronomical investigations in the energy range of 10¹²‒10¹⁷ eV, carried out without application of highly expensive Cherenkov detectors, at the detectors of the Tien Shan high-altitude scientific station. We consider the strategy of using the Tien Shan detector complex as a gamma-astronomy installation: combination of information about the parameters of extensive air showers (EAS's) provided by the detectors of the shower installation with the data on the direction of EAS axis determined by the detectors of the shower front delay measurement system, as well as a special selection of the EAS events with a small number of muons and a low neutron content and acquisition of information from the gamma-block of the ionization calorimeter. Prospects for upgrading the complex in order to expand the energy range up to gamma-shower energies of 10¹⁸ eV are considered. [ABSTRACT FROM AUTHOR]