TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4943 SUBJECT: GRB060331: Swift/UVOT upper limits DATE: 06/04/03 10:10:57 GMT FROM: Patricia Schady at MSSL/Swift P. Schady (UCL-MSSL), on behalf of the Swift/UVOT team The Swift/UVOT observed the field of HETE II transient H4043 (Fenimore et al. GCN 4938) at two separate epochs starting at 16:53 UT and 18:29 UT. A 575s coadded exposure from the first epoch of observations taken in white reveals no new source in the field of view down to a 5-sigma magnitude upper limit of 19.9. In both epochs no source is detected in summed images from any of the filters used down to the following 5-sigma upper limits. 1st Epoch Filter Date Obs. Exp (s) 5sigUL(mag) B 17:08:07 UT 885 20.3 U 16:52:56 UT 885 20.0 White 17:23:18 UT 575 19.9 2nd Epoch Filter Date Obs. Exp (s) 5sigUL(mag) B 18:59:13 UT 605 19.8 U 18:44:02 UT 885 20.0 UVW1 18:28:55 UT 886 19.4 where Date Obs. is the time of the beginning of the observations. These magnitudes are not corrected for Galactic extinction; E(B-V)=0.148.