TITLE: GCN CIRCULAR NUMBER: 28810 SUBJECT: GRB 201029A: Swift/UVOT Upper Limits DATE: 20/10/30 17:25:08 GMT FROM: Frank Marshall at Swift/UVOT F. E. Marshall (NASA/GSFC) and S. Dichiara (NASA/GSFC/UMCP) report on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of GRB 201029A 131 s after the BAT trigger (Dichiara et al., GCN Circ. 28803). No optical afterglow consistent with the XRT position (Beardmore et al. GCN Circ. 28806) 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 131 281 147 >20.6 u_FC 289 539 246 >19.9 white 131 1708 412 >21.4 v 619 1759 127 >19.2 b 545 1858 136 >19.9 u 289 1833 362 >20.0 w1 842 1808 97 >19.5 The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.02 in the direction of the burst (Schlegel et al. 1998).