American Astronomical Society, Astrophysical Journal, 2(542), p. 740-749, 2000
DOI: 10.1086/317054
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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. ; Comment: 32 pages, 9 figures, uses aasms4 and epsfig style files. Accepted for publication in The Astrophysical Journal