A Potential Supernova Remnant-X-Ray Binary Association in M31

The well-studied X-ray/optical/radio supernova remnant (SNR) DDB 1-15 (CXOM31 J004327.8+411829; r3-63) in M31 has been investigated with archival XMM-Newton and Chandra observations. The timing data from XMM-Newton reveal a power density spectrum (PDS) characteristic of accreting compact objects in X-ray binaries (XRBs). The PDS shows features typical of Roche lobe overflow accretion, hinting that the XRB is low mass. The Chandra observations resolve the SNR into a shell and show a variable count rate at the 94% confidence level in the northwest quadrant. Together, these XMM-Newton and Chandra data suggest that there is an XRB in the SNR r3-63 and that the XRB is located in the northwestern portion of the SNR. The currently available X-ray and optical data show no evidence that the XRB is high mass. If the XRB is low mass, r3-63 would be the first SNR found to contain a low-mass X-ray binary.