TITLE: GCN CIRCULAR NUMBER: 13461 SUBJECT: GRB 120712A: Swift/UVOT Detection DATE: 12/07/13 12:15:47 GMT FROM: Samantha Oates at MSSL S. R. Oates (MSSL-UCL) and M. J. Page (MSSL-UCL) report on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of GRB 120712A 95 s after the BAT trigger (Page et al., GCN Circ. 13454). A source consistent with the XRT position (Osborne et al., GCN Circ. 13456) and the optical position reported by GROND (Elliott et al., GCN Circ. 13457) is detected in the initial UVOT exposures. The preliminary UVOT position is: RA (J2000) = 11:18:21.25 = 169.58854 (deg.) Dec (J2000) = -20:02:01.7 = -20.03380 (deg.) with an estimated uncertainty of 0.50 arc sec. (radius, 90% confidence). Preliminary detections and 3-sigma upper limits 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 (FC) 95 245 147 16.95 +/- 0.03 white 861 1010 150 18.93 +/- 0.09 v 637 657 19 16.79 +/- 0.15 b 563 18691 1160 >21.8 u 308 35517 2569 >22.1 w1 686 35216 3108 >22.0 m2 4818 41481 3296 >22.1 w2 613 40167 2931 >22.1 The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.04 in the direction of the burst (Schlegel et al. 1998).