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Multiwavelength Examination of the COS-B Field 2CG 075+00 Yields a Blazar Identification for 3EG J2016+3657

R. Mukherjee·E. V. Gotthelf·J. Halpern·M. Tavani
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Abstract

We present a high-energy study of the intriguing COS-B gamma-ray field, 2CG 075+00, in order to search for possible counterparts. New EGRET data show that the COS-B emission probably corresponds to two localized gamma-ray sources, 3EG J2016+3657 and 3EG J2021+3716. Spectral fits to these EGRET sources, assuming a power-law model, yield photon indices of ~ 2 for each object. We examine archival ROSAT and ASCA X-ray data which overlap both EGRET error boxes, and find several point sources in the region to a flux limit of approximately 6.5 x 10^{-13} erg cm^{-2} s^{-1}. We conclude that the most probable candidate for 3EG J2016+3657 is the compact, variable, flat-spectrum radio and millimeter source B2013+370 (G74.87+1.22) which has blazar-like properties. The other source, 3EG J2021+3716, remains unidentified.

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R. Mukherjee, E. V. Gotthelf, J. Halpern, M. Tavani. 2000-05-24. Multiwavelength Examination of the COS-B Field 2CG 075+00 Yields a Blazar Identification for 3EG J2016+3657. https://doi.org/10.1086/317054

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