TITLE: GCN CIRCULAR NUMBER: 42588 SUBJECT: GRB 251103B: Swift/UVOT Upper Limits DATE: 25/11/05 13:58:01 GMT FROM: Alice Breeveld at MSSL-UCL <a.breeveld@ucl.ac.uk> A.A. Breeveld (UCL-MSSL) and S. Lanava (PSU) report on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of GRB 251103B 140 s after the BAT trigger (Lanava et al., GCN Circ. 42556). No optical afterglow consistent with the enhanced XRT position (Evans et al., GCN Circ. 42558)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 u_FC 140 390 246 >20.2 white 420 1363 245 >21.1 v 470 1413 117 >19.0 b 395 1339 97 >19.8 w1 519 1462 97 >18.8 m2 494 1437 117 >18.8 w2 445 1389 117 >19.1 The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.256 in the direction of the burst (Schlegel et al. 1998). View this GCN Circular online at https://gcn.nasa.gov/circulars/42588. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...