GCN Circular 4839
P. Schady (PSU/MSSL-UCL), J.R. Cummings (NASA/ORAU), P.Brown (PSU), A. Cucchiara (PSU) on behalf of the Swift/UVOT team The Swift/UVOT began observing the field of GRB 060223b at 16:23:16 UT on 24th February 2006, ~22hrs after the BAT trigger (Cummings et al. GCN 4821). Due to the proximity of a Mira variable star (~5th mag) observations were not made in the V or B filters. No source is detected at the refined XRT position (Perri et al. GCN 4835) in any of the other filters. The 3 sigma upper limits from a set of three coadded exposures in each filter are as follows: Filter T_mid(hrs) Exp(s) 3sigUL(mag) U 22.6 2300 20.5 UVW1 22.0 2522 20.8 UVM2 21.8 2524 21.1 UVW2 21.1 2524 21.3 T_mid is the mid-time of the set of coadded images relative to the time since the BAT trigger. We note that this is a very crowded field with a high level of Galactic extinction (E(B-V) = 0.393). All reported magnitudes are uncorrected for Galactic extinction.