TITLE: GCN CIRCULAR NUMBER: 8012 SUBJECT: GRB 080723A: Swift/UVOT Upper Limits DATE: 08/07/24 14:32:06 GMT FROM: Stephen Holland at USRA/NASA/GSFC/SSC S. T. Holland (CRESST/GSFC/USRA) and M. Stamatikos (NASA/ORAU) report on the behalf of the Swift UVOT team: The Swift/UVOT observed the field of GRB 080723A starting 68 s after the BAT trigger (Stamatikos et al. 2008, GCN Circ. 8000). We do not find any source, in any of the UVOT observations, at the UVOT-enhanced XRT position of the afterglow (Beardmore 2008, GCN Circ. 8001). The 3-sigma upper limits for detecting a source at this location in the co-added images are: Filter T_start T_stop Exp(s) Mag (3-sigma upper limit) ----------------------------------------------------------------- v 194 6260 1040 >20.1 b 674 7080 451 >20.6 u 649 6874 471 >20.4 uvw1 625 6670 469 >20.3 uvm2 600 6465 467 >20.1 uvw2 704 7468 430 >20.4 white 88 7284 628 >21.4 ----------------------------------------------------------------- The quoted upper limits have not been corrected for the expected Galactic extinction along the line of sight corresponding to a reddening of E_{B-V} = 1.3 mag. All photometry is on the UVOT flight system described in Poole et al. (2008, MNRAS, 383, 627).