TITLE: GCN CIRCULAR NUMBER: 14619 SUBJECT: GRB 130508A: Swift/UVOT Upper Limits DATE: 13/05/10 20:39:01 GMT FROM: Stephen Holland at STScI S. T. Holland (STScI) reports on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of GRB 130508A starting 136 s after the BAT trigger (Holland et al. 2013, GCNC 14607). We do not detect any new source consistent with the UVOT-enhanced XRT position (Evans 2013, GCNC 14614) in any of the UVOT exposures. Preliminary 3-sigma upper limits using the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the finding chart (FC) exposures and initial summed exposures are presented below. Filter TSTART TSTOP Exposure Mag ------------------------------------------------- white (FC) 136 285 147 >20.8 u (FC) 296 545 246 >19.8 ------------------------------------------------- v 4416 5642 393 >20.0 b 551 6336 288 >20.5 u 296 6257 639 >20.5 uvw1 4417 6052 393 >20.3 uvm2 4212 5847 393 >20.3 uvw2 3801 5437 393 >20.5 white 136 5231 344 >21.5 ------------------------------------------------- The quoted upper limits have not been corrected for the expected extinction due to the Galactic reddening along the line of sight to this burst of E(B-V) = 2.54 mag (Schlafly et al. 2011, ApJS, 737, 103).