TITLE: GCN CIRCULAR NUMBER: 16219 SUBJECT: GRB 140506A: Swift/UVOT Detection DATE: 14/05/07 17:00:49 GMT FROM: Mike Siegel at PSU/Swift MOC M. H. Siegel (PSU) and B. P. Gompertz (U Leicester) report on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of GRB 140506A 108 s after the BAT trigger (Gompertz et al., GCN Circ. 16214). A source consistent with the XRT position (Osborne et al. GCN Circ. 16215) is detected in the initial UVOT exposures. The preliminary UVOT position is: RA (J2000) = 18:27:06.04 = 276.77516 (deg.) Dec (J2000) = -55:38:08.7 = -55.63575 (deg.) with an estimated uncertainty of 0.43 arc sec. (radius, 90% confidence). Preliminary detections and 3-sigma upper limits using the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first and second orbits are: Filter T_start(s) T_stop(s) Exp(s) Mag white (fc) 108 257 147 17.19+-0.03 white 108 1545 390 17.82+-0.05 white 6078 6278 196 20.07+-0.14 white 11748 12655 885 21.52+-0.26 v 650 1576 98 >18.87 v 5053 6688 393 19.82+-0.32 b 576 1520 97 19.40+-0.30 b 5873 7334 221 >20.57 u (fc) 320 570 245 17.34+-0.07 u 320 1496 323 17.50+-0.07 u 5668 7303 393 20.04+-0.34 uvw1 700 1471 77 18.60+-0.29 uvw1 5463 7098 393 >20.29 uvm2 675 1446 97 >18.96 uvm2 5257 6893 393 >20.17 uvw2 626 1570 116 >19.41 uvw2 6284 6484 196 >19.97 The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.09 in the direction of the burst (Schlegel et al. 1998).