NOTE: uvot_fluxes_wget.pl vrs. 2018-01-16 fem at 180805d20h35m30s379412usUT NOTE: Source region spec. is: 167.56625 -45.33222 4" NOTE: Used archived XRT position of 167.56625 -45.33222 4.00 NOTE: position reference is GCN_Circulars-23075 =========== Draft Upper Limit Circular ======== GRB 180805A: Swift/UVOT Upper Limits ***UBS*** (***INSTITUTION***) and P. D'Avanzo (INAF-OAB) report on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of GRB 180805A 90 s after the BAT trigger (D'Avanzo et al., GCN Circ. 23074). No optical afterglow consistent with the XRT position (Beardmore et al. GCN Circ. 23075) 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 90 239 147 >19.8 u_FC 302 552 246 >19.5 white 90 1029 334 >20.6 v 632 1080 58 >18.0 b 558 1172 52 >19.1 u 302 1153 285 >19.6 w1 681 1129 58 >19.3 m2 656 1104 39 >19.4 w2 608 1055 58 >18.1 The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.19 in the direction of the burst (Schlegel et al. 1998).