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BL Lac: A New Ultrahigh-Energy Gamma-Ray Source

Yu. I. Neshpor·N. N. Chalenko·A. A. Stepanian·O. R. Kalekin·N. A. Jogolev·V. P. Fomin·V. G. Shitov
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Abstract

The active galactic nucleus BL Lac was observed with the Gt-48 atmospheric Cherenkov detector of the Crimean Astrophysical Observatory from July 23-September 1, 1998, in order to search for ultrahigh-energy gamma-ray (>1 TeV) emission. The object was in the field of view of the detector for more than 24 hours. The source was detected with a high level of confidence (7.2 sigma), with a flux equal to (2.1+/-0.4)x10^{-11} photons cm^{-2}s^{-1}.

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Yu. I. Neshpor, N. N. Chalenko, A. A. Stepanian, O. R. Kalekin, N. A. Jogolev, V. P. Fomin, V. G. Shitov. 2001-11-22. BL Lac: A New Ultrahigh-Energy Gamma-Ray Source. https://doi.org/10.1134/1.1361316

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