TITLE: GCN CIRCULAR NUMBER: 8224 SUBJECT: GRB080913: Swift/UVOT Upper Limits DATE: 08/09/13 16:40:12 GMT FROM: Samantha Oates at MSSL S. R. Oates and P. Schady report on behalf of the Swift/UVOT team. The Swift/UVOT began settled observations of the field of GRB 080913 starting 105s after the BAT trigger (Schady et al., GCN 8217). We do not detect an afterglow in any of the UVOT filters inside the UVOT-enhanced XRT error circle (Beardmore et al., GCN 8219). The 3 sigma upper limits for the finding charts (fc) and summed images are given below: Filter T_start(s) T_stop(s) Expo(s) Magnitude (3 sigma UL) ----------------------------------------------------------------- White (fc) 105 205 98 >20.92 White 105 1964 238 >21.26 v (fc) 211 611 393 >20.08 v 211 1858 865 >20.39 b 691 1957 97 >19.62 u 666 1932 117 >19.36 w1 641 1907 117 >19.48 m2 616 1882 78 >18.84 w2 721 1833 58 >18.99 ---------------------------------------------------------------- The above magnitudes are not corrected for the Galactic extinction corresponding to a reddening of E_{B-V} = 0.04 mag (Schlegel et al., 1998, ApJS, 500, 525). The photometry is on the UVOT flight system described in Poole et al. (2008,MNRAS,383,627).