TITLE: GCN CIRCULAR NUMBER: 17151 SUBJECT: GRB 141207A: Swift-UVOT Observations DATE: 14/12/08 22:35:11 GMT FROM: Mike Siegel at PSU/Swift MOC GRB 141207A: Swift-UVOT Observations M. H. Siegel (PSU) and A. Amaral-Rogers (U. Leicester) report on behalf of the Swift-UVOT team: We have observed the area around the Fermi-LAT GRB 141207A (Arimoto et al., GCN Circ. 17146), in 4 UVOT fields starting at 07:59:28 UT, 12 hours and 48 minutes after Fermi/LAT detection. There is an optical source at a position of RA,Dec=160.06441, 3.89477, which is equivalent to: RA (J2000) = 10h 40m 15.46s Dec (J2000) = +03d 53' 41.2” with an uncertainty of 0.1” (radius, 90% confidence). This source is 5.6” from the position of the XRT source (Amaral-Rogers and Evans, GCN Circ. 17149) and shows up as a marginal detection in the DSS. It is possibly unrelated to the burst. Follow-up observations will be needed to confirm its nature. The preliminary u magnitude using the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) is 19.91+-0.17.