TITLE: GCN CIRCULAR NUMBER: 27006 SUBJECT: GRB 200205B: Swift/UVOT Detection DATE: 20/02/07 02:46:45 GMT FROM: Kira Simpson at PSU GRB 200205B: Swift/UVOT Detection K. K. Simpson (PSU) 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 200205B 352 s after the BAT trigger (Evans et al., GCN Circ. 26993). A source consistent with the XRT position (Evans et al. GCN Circ. 26993) is detected in the initial UVOT exposures. The preliminary UVOT position is: RA (J2000) = 07:11:09.15 = 107.78812 (deg.) Dec (J2000) = -56:29:15.3 = -56.48759 (deg.) with an estimated uncertainty of 0.42 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 early exposures are: Filter T_start(s) T_stop(s) Exp(s) Mag white 6386 6586 196 18.92+-0.10 white 383 1042 478 16.81+-0.03 v 540 733 38 16.88 +/- 0.17 b 638 833 38 17.74 +/- 0.15 u 614 808 38 17.25 +/- 0.16 w1 589 783 38 16.88+-0.20 m2 564 758 38 17.12 +/- 0.28 w2 689 1056 46 >17.77 The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.11 in the direction of the burst (Schlegel et al. 1998).