TITLE: GCN CIRCULAR NUMBER: 11907 SUBJECT: GRB110407A: UVOT Upper Limits DATE: 11/04/08 12:05:39 GMT FROM: Samantha Oates at MSSL S. R. Oates (MSSL-UCL) & C. W. Wolf (PSU) report on behalf of the Swift-UVOT team The Swift/UVOT began settled observations of the field of GRB 110407A 168s after the trigger (Wolf et al., GCN Circ. 11895). We do not detect a source at the position of the X-ray (Evans et al., GCN Circ. 11896, 11903) or optical afterglow reported by Lulin (Chuang et al, GCN Circ. 11899, 11901), NOT (Malesani et al., GCN Circ. 11904) and GROND (Kann et al, GCN Circ. 11906). Preliminary magnitudes using the UVOT photometric system (Poole et al. 2008,MNRAS, 383, 627) for the finding chart (FC) and summed exposures at the location of the optical afterglow are: Filter T_start(s) T_stop(s) Exp(s) Mag/3sigUL ##################################################### wh (FC) 168 317 147 >20.82 wh 607 6514 580 >21.59 u (FC) 327 577 246 >20.11 u 732 6104 413 >20.41 v 658 6873 382 >19.74 b 583 6309 432 >20.75 uvw1 708 5899 413 >20.34 uvm2 5493 5693 197 >19.75 uvw2 808 6719 413 >20.68 ##################################################### The values quoted above are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.03 in the direction of the burst (Schlegel et al. 1998).