TITLE: GCN CIRCULAR NUMBER: 22937 SUBJECT: GRB 180709A: Swift/UVOT Upper Limits DATE: 18/07/09 20:38:53 GMT FROM: Alice Breeveld at MSSL-UCL A. A. Breeveld (UCL-MSSL), S. W. K. Emery (UCL-MSSL) and F. E. Marshall (NASA/GSFC) report on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of GRB 180709A 115 s after the BAT trigger (Marshall et al., GCN Circ. 22930). No optical afterglow consistent with the XRT position (Beardmore et al., GCN Circ. 22933) 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 115 264 147 >20.5 u_FC 273 523 246 >19.6 v 604 797 39 >18.0 b 529 723 39 >19.0 uvw1 654 846 39 >17.7 The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 2.72 in the direction of the burst (Schlegel et al. 1998).