TITLE: GCN CIRCULAR NUMBER: 15275 SUBJECT: GRB 130929A: Swift/UVOT Upper Limits DATE: 13/09/30 18:07:07 GMT FROM: Frank Marshall at GSFC F. E. Marshall (NASA/GSFC) reports on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of GRB 130929A 280 s after the BAT trigger (Marshall et al., GCN Circ. 15269). No optical afterglow consistent with the XRT position (Goad et al. GCN Circ. 15271) 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 280 430 147 >21.0 white 280 1008 334 >21.4 v 586 4628 236 >19.7 b 512 705 39 >19.0 u 487 10592 709 >20.6 w1 462 6710 255 >19.6 m2 437 6505 308 >19.7 w2 562 4423 236 >19.7 The magnitudes in the table are not corrected for the large Galactic extinction in the direction of the burst (Schlegel et al. 1998).