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We report observations with the Chandra X-ray Observatory of a field in thegamma$-Cygni supernova remnant (SNR78.2+2.1) centered on the cataloged locationof the unidentified, bright gamma-ray source 3EG J2020+4017. In this search foran X-ray counterpart to the gamma-ray source, we detected 30 X-ray sources. Ofthese, we found 17 strong-candidate counterparts in optical (visible throughnear-infrared) cataloged and an additional 3 through our optical observations.Based upon colors and (for several objects) optical spectra, nearly all theoptically identified objects appear to be reddened main-sequence stars. None ofthe X-ray sources with an optical counterpart is a plausible X-ray counterpartto 3EG J2020+4017 --if that gamma-ray source is a spin-powered pulsar. Many ofthe 10 X-ray sources lacking optical counterparts are likely (extragalactic)active galactic nuclei, based upon the sky density of such sources. Althoughone of the 10 optically unidentified X-ray sources could be the gamma-raysource, there is no auxiliary evidence supporting such an identification.Comment: 32 pages, 8 figures, submitted to Ap

A Search for the X‐Ray Counterpart of the Unidentified γ‐Ray Source 3EG J2020+4017 (2CG078+2)