Studying X-Ray Emission from a Nearby Isolated Black Hole

Straightforward interpretation of the spectacular new microlensingevent OGLE1999BUL32 indicates that the lens is either a virgul130Msun black hole at 500 pc or a virgul30 Msun black hole at 6kpc. We request 50 ksec EPIC camera observations that will yield alimiting Xray sensitivity which is more than two orders of magnitudedeeper than the best existing limits. If detected, the observationswill allow us to distinguish between the two possible lens distancesand provide a powerful test of models for accretion onto isolatedblack holes. truncated!, Please see actual data for full text [truncated!, Please see actual data for full text]