TITLE: GCN CIRCULAR NUMBER: 32488 SUBJECT: GRB 220826A: Swift/UVOT Detection DATE: 22/08/26 18:47:37 GMT FROM: Paul Kuin at MSSL N. P. M. Kuin (UCL-MSSL) and R. Caputo (GSFC) report on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of GRB 220826A 91 s after the BAT trigger (Caputo et al., GCN Circ. 32484). A source consistent with the XRT position (Beardmore et al. GCN Circ. 32485) is detected in the initial UVOT exposures. The preliminary UVOT position is: RA (J2000) = 13:45:38.51 = 206.41047 (deg.) Dec (J2000) = -44:02:19.2 = -44.03866 (deg.) with an estimated uncertainty of 0.45 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 91 240 147 18.12 +/- 0.05 v 632 827 39 >18.4 b 559 753 39 >18.6 u 303 553 246 18.69 +/- 0.13 w1 682 702 19 >17.7 m2 831 851 19 >17.8 w2 608 802 39 >19.2 The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.110 in the direction of the burst (Schlegel et al. 1998).