TITLE: GCN CIRCULAR NUMBER: 18587 SUBJECT: GRB 151111A: Swift/UVOT upper limits DATE: 15/11/12 13:57:55 GMT FROM: Massimiliano de Pasquale at IASF-Palermo M. De Pasquale, S. Emery (UCL-MSSL) and L. M. McCauley (PSU) report on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of GRB 151111A 81 s after the BAT trigger (McCauley et al., GCN Circ. 18578). No optical afterglow consistent with the XRT position (Goad et al. GCN Circ. 18579) is detected in the initial UVOT exposures. 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 are: Filter T_start(s) T_stop(s) Exp(s) Mag white_FC 81 231 147 >20.9 u_FC 293 543 246 >19.7 white 81 6778 519 >21.7 v 622 7094 339 >19.7 b 549 6573 235 >20.6 u 293 6367 442 >19.7 w1 671 6163 216 >20.0 m2 5757 5957 197 >19.7 w2 772 6984 413 >20.6 The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.01 in the direction of the burst (Schlegel et al. 1998).