TITLE: GCN CIRCULAR NUMBER: 11032 SUBJECT: GRB 100802A: Possible Swift/UVOT Detection of Optical Afterglow DATE: 10/08/02 06:21:36 GMT FROM: Mike Siegel at PSU/Swift MOC M. H. Siegel (PSU) and E. Troya (NASA/GSFC/ORAU) report on behalf of the Swift/UVOT team: UVOT took a finding chart exposure of 250 seconds with the U filter starting 301 seconds after the BAT trigger. There is a candidate afterglow in the rapidly available 2.7'x2.7' sub-image at RA(J2000) = 00:09:52.47 = 2.46862 DEC(J2000) = +47:45:19.1 = 47.75531 with a 90%-confidence error radius of about 0.78 arc sec. This position is 4.3 arc sec. from the center of the XRT error circle. The estimated magnitude is 19.56 with a 1-sigma error of about 0.21. No correction has been made for the expected extinction corresponding to E(B-V) of 0.12.