TITLE: GCN CIRCULAR NUMBER: 17598 SUBJECT: GRB 150317A: Swift/UVOT Upper Limits DATE: 15/03/18 03:49:56 GMT FROM: Margaret Chester at PSU M. M. Chester (PSU) and M. H. Siegel (PSU) report on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of GRB 150317A 126 s after the BAT trigger (Siegel et al., GCN Circ. 17592). Due to the location of the counterpart (Evans and Goad GCN Circ. 17594, Butler et al. GCN Circ. 17595) in the wings of the nearby bright star (V~11.2), we cannot report a certain detection. We therefore provide preliminary 3-sigma upper limits using the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first finding chart (FC) exposure and subsequent exposures, as follows: Filter T_start(s) T_stop(s) Exp(s) Mag u_FC 126 376 246 >19.6 v 432 6158 334 >19.2 b 381 6978 571 >20.4 u 126 6773 739 >20.2 w1 481 6568 335 >19.6 m2 457 6363 255 >19.4 w2 407 7037 384 >20.0 The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.03 in the direction of the burst (Schlegel et al. 1998).