BLAZAR 3C 66A - ANOTHER EXTRAGALACTIC SOURCE OF ULTRA-HIGH-ENERGY GAMMA-RAY PHOTONS

The observations of the object 3C 66A which were carried out with the GT-48 gamma-ray telescope at the Crimean Astrophysical Observatory in November-December 1996 revealed a flux of ultra-high-energy (>10(12) e V) gamma-ray photons from this blazar. According to preliminary estima tes, the photon flux is (3 +/-1) x 10(-11) photons cm(-2) s(-1). The b lazar 3C 66A is the third extragalactic object from which a flux of ul trahigh-energy gamma-ray photons was detected. Fluxes of gamma-ray pho tons were previously detected from the galaxies Mk 421 and Mk 501 at t he Whipple observatory This result provides further evidence that acti ve processes proceed in blazars which are accompanied by the generatio n of cosmic rays responsible for the emission of gamma-ray photons.