TITLE: GCN CIRCULAR NUMBER: 17925 SUBJECT: GRB 150615A: Swift/UVOT Detection DATE: 15/06/15 13:44:32 GMT FROM: Samantha Oates at MSSL S. R. Oates (IAA-CSIC/UCL-MSSL) and E. Troja (NASA/GSFC/UMCP) report on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of GRB 150615A 122 s after the BAT trigger (Troja et al., GCN Circ. 17923). A faint source consistent with the enhanced XRT position (Beardmore et al. GCN Circ. 17924) is detected in the combined white exposures. Preliminary detection 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 122 1532 392 20.64 +/- 0.19 v 611 1409 97 >18.3 b 536 1507 97 >19.9 u 280 1482 324 >20.2 w1 660 1458 97 >19.2 m2 635 1433 97 >18.9 w2 586 1557 117 >19.4 The magnitudes in the table are not corrected for the significant Galactic extinction due to the reddening of E(B-V) = 0.33 in the direction of the burst (Schlegel et al. 1998).