TITLE: GCN CIRCULAR NUMBER: 16380 SUBJECT: GRB 140610A: Swift/UVOT Upper Limits DATE: 14/06/11 12:33:01 GMT FROM: Alice Breeveld at MSSL-UCL A. A. Breeveld (UCL-MSSL) and P. A. Evans (U Leicester) report on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of GRB 140610A 3145 s after the BAT trigger (Evans et al., GCN Circ. 16375). No optical afterglow consistent with the XRT position (Kennea et al. GCN Circ. 16376) is detected in the initial UVOT exposures. Preliminary 3-sigma upper limits using the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first finding chart (FC) exposure and subsequent exposures are: Filter T_start(s) T_stop(s) Exp(s) Mag white_FC 3145 3295 147 >21.1 white 3145 9879 1229 >22.3 v 3301 4937 393 >19.9 b 4122 5685 320 >20.6 u 3916 5552 393 >20.5 w1 3712 5347 393 >20.5 m2 3506 5142 393 >20.3 w2 4533 10719 1017 >21.3 The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 2.56 in the direction of the burst (Schlegel et al. 1998).