Long-term observations of the Cyg X-3 and λCygni SNR at ultrahigh energies by SHALON mirror Cherenkov telescopes

Abstract

The Cygnus X region contains a number of powerful sources of radio and X-ray radiation which are also considered as potential sources of high and ultrahigh-energy radiation. One of such sources is the massive binary system Cyg X-3 systematically observed by the SHALON telescope from 1995 to the present. The results of Cyg X-3 observations are presented by γ-ray spectra and images at energies of 800 GeV-85 TeV. In the field of the SHALON telescope, an ultrahigh-energy γ-ray source was detected, whose position is ∼2° from Cyg X-3; its coordinates coincide with coordinates of the known source of radio and X-ray radiation, i.e., the γCygni SNR supernova remnant. The γCygni SNR spectra, spectral energy distribution, and image according to the SHALON telescope data are presented in the energy range of 800 GeV-50 TeV.