TITLE: GCN CIRCULAR NUMBER: 10220 SUBJECT: GRB 091130B: Swift/UVOT Upper Limits DATE: 09/12/01 05:22:33 GMT FROM: Erik Hoversten at Swift/Penn State E. A. Hoversten (PSU) and J. L. Racusin (NASA/GSFC) report on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of GRB 091130B 95s after the BAT trigger (Racusin et al., GCN 10214). We do not detect any source at the enhanced Swift XRT position (Goad et al. GCN 10218). UVOT magnitude 3-sigma upper limits are reported in the following table: Filter T_start T_stop Exp(s) Mag (3-sigma upper limit) ------------------------------------------------------------- white 95 230 132 > 20.20 white 4517 4717 196 > 20.97 v 3492 3692 196 > 19.38 b 4313 4512 196 > 20.31 u 4107 4307 196 > 19.91 uvw1 3903 4102 196 > 19.88 uvm2 3697 3897 196 > 19.76 uvw2 4723 4923 196 > 19.98 The quoted upper limits have not been corrected for the expected Galactic extinction along the line of sight of E_(B-V) = 0.01 mag (Schlegel et al. 1998). All photometry is on the UVOT photometric system described in Poole et al. (2008, MNRAS, 383, 627).