TITLE: GCN CIRCULAR NUMBER: 9495 SUBJECT: GRB 090607: Swift/UVOT Upper Limits DATE: 09/06/07 16:42:02 GMT FROM: Peter Curran at MSSL P.A. Curran (UCL-MSSL) and F. Marshall (NASA/GSFC) report on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of GRB 090607 75 s after the BAT trigger (Marshall et al., GCN Circ. 9491). No optical afterglow consistent with the XRT position (Marshall et al., GCN Circ. 9491) is detected in the initial UVOT exposures. Preliminary 3-sigma upper limits using the UVOT photometric system (Poole et al. 2008, MNRAS, 383, 627) for the first finding chart (FC) exposure and subsequent exposures are: Filter T_start(s) T_stop(s) Exp(s) Mag uvw1 12715 13943 1209 >20.8 u 75 1233 1140 >21.2 v 11448 12707 1239 >20.4 The values quoted above are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.02 in the direction of the burst (Schlegel et al. 1998).