TITLE: GCN CIRCULAR NUMBER: 16198 SUBJECT: GRB 140430A: Swift/UVOT Observations DATE: 14/05/01 11:42:29 GMT FROM: Alice Breeveld at MSSL-UCL A. A. Breeveld (UCL-MSSL) and M. H. Siegel (PSU) report on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of GRB 140430A 183 s after the BAT trigger (Siegel et al., GCN Circ. 16190). A fading source consistent with the refined XRT position (Evans et al. GCN Circ. 16195) is confirmed in the initial UVOT exposures. The detection in the uvw1 filter, but not in uvm2 and uvw2 is consistent with the redshift of 1.6 given by Kruehler et al., (GCN Circ. 16194). Preliminary detections and 3-sigma upper limits using the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the early exposures are: Filter T_start(s) T_stop(s) Exp(s) Mag white_FC 183 333 147 18.17 ± 0.09 white 4020 4220 197 19.61 ± 0.17 v 417 4630 216 >18.6 b 3815 4015 197 19.77 ± 0.34 u 10431 10933 490 19.46 ± 0.19 uvw1 6178 10424 966 20.40 ± 0.31 uvm2 442 4835 216 >19.9 uvw2 393 4425 216 >19.4 The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.14 in the direction of the burst (Schlegel et al. 1998).