TITLE: GCN CIRCULAR NUMBER: 29492 SUBJECT: GRB 210212A: Swift/UVOT Upper Limits DATE: 21/02/12 14:53:24 GMT FROM: Paul Kuin at MSSL N. P. M. Kuin (UCL-MSSL) and E. Troja (NASA/GSFC/UMCP) report on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of GRB 210212A 112 s after the BAT trigger (Troja et al., GCN Circ. 29487). No optical afterglow consistent with the XRT position (Beardmore et al. GCN Circ. 29489) 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 112 262 147 >20.6 u_FC 271 520 246 >20.3 white 112 930 242 >20.8 v 600 4588 236 >19.0 b 526 720 39 >19.3 u 271 868 285 >20.4 w1 650 4851 90 >19.1 m2 626 4793 235 >19.7 w2 93 4383 245 >19.7 The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.094 in the direction of the burst (Schlegel et al. 1998).