TITLE: GCN CIRCULAR NUMBER: 22327 SUBJECT: GRB 180111A: Swift/UVOT Detection DATE: 18/01/13 13:53:26 GMT FROM: Jeffrey Gropp at PSU J. D. Gropp (PSU) and A. Y. Lien (GSFC/UMBC) report on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of GRB 180111A 98 s after the BAT trigger (Lien et al., GCN Circ. 22318). A fading source consistent with the XRT position (Evans et al. GCN Circ. 22319) is detected in the initial UVOT exposures. Preliminary detections using the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the early exposures are: Filter T_start(s) T_stop(s) Exp(s) Mag white 84 233 147 19.95+-0.21 white 86 6202 552 20.37+-0.16 v 64 5181 206 >19.23 b 4365 6002 393 >20.60 u 296 5795 639 20.25+-0.35 w1 5391 5591 196 >19.50 m2 650 670 19 >17.15 w2 4776 6407 393 19.60+-0.27 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).