TITLE: GCN CIRCULAR NUMBER: 18662 SUBJECT: GRB151205B: Initial UVOT observations DATE: 15/12/05 23:09:33 GMT FROM: Lea Hagen at PSU L. M. Z. Hagen (PSU) reports on behalf of the Swift/UVOT team: UVOT took a finding chart exposure of 150 seconds with the White filter starting 3131 seconds after the BAT trigger (Marshall et al., GCN Circ. 18659). No credible afterglow candidate has been found in the initial data products. The 2.7'x2.7' sub-image covers 25% of the BAT error circle. The typical 3-sigma upper limit has been about 19.6 mag. The 8'x8' region for the list of sources generated on-board covers 100% of the BAT error circle. The list of sources is typically complete to about 18 mag. No correction has been made for the expected extinction corresponding to E(B-V) of 0.02. [GCN OPS NOTE(20jan16): Per author's request, the burst name in the Subject-line was changed from "A" to "B".]