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AX J2049.6+2939 is a compact X-ray source in the vicinity of the southernblow-up region of the Cygnus Loop supernova remnant (Miyata et al. 1998a). Thissource was the brightest X-ray source inside the  Cygnus Loop observed during the ASCA survey project. The X-ray spectrum waswell fitted by a power-law function with a photon index of $-2.1  \pm 0.1$. Short-term timing analysis was performed and no coherent pulsationwas found. Follow-up observations with ASCA have revealed a large variation inX-ray intensity by a factor of $\simeq$ 50, whereas the spectral shape did notchange within the statistical uncertainties. In the second ASCA observation, wefound another X-ray source, AX J2050.0+2941, at the north east of AX  J2049.6+2939. During the three ASCA observations, the X-ray intensity of AXJ2050.0+2941 varied by a factor of $\simeq$4. No coherent pulsations could befound for AX J2050.0+2941.  We have performed optical photometric and spectroscopic observations in thevicinity of AX J2049.6+2939 at the Kitt Peak National Observatory  (KPNO). As a result, all objects brighter than $B$-band magnitude of 22 inthe error box can be identified with normal stars. Combined with the  X-ray results and the fact that there are no radio counterparts, AX  J2049.6+2939 is not likely to be either an ordinary rotation-powered pulsaror an AGN. The nature of AX J2049.6+2939 is still unclear and furtherobservations over a wide energy band are strongly required.  As to AX J2050.0+2941, the long-term X-ray variability and the radiocounterpart suggests that it is an AGN.Comment: 23 pages, 4 figures, Accepted for publication by Astrophysical  Journa

On the Nature of AX J2049.6+2939/AX J2050.0+2914