090154

Radio and X-ray imaging of a newly discovered comma transient X-ray binary reveals a supernova remnant. High extinction prevents a mass function for the binary comma but every available diagnostic signals that the primary is a black hole. IR imaging suggests a high- or intermediate-mass companion star. The structure of the SNR is particularly clear in radio comma and similar to Cas A. However comma the X-ray structure is not clearly revealed in a prior XMM-Newton snapshot. We request 90 ks of good exposure openPar150 ks totalclosePar to reveal the X-ray morphology of the SNR comma obtain basic age constraints from spectral modeling comma and to make a test of the remnant type that could reveal the X-ray binary-SNR association as spurious.