TITLE: GCN CIRCULAR NUMBER: 36891 SUBJECT: GRB 240715A: Swift/UVOT observations of the XRT sources. DATE: 24/07/16 17:17:40 GMT FROM: Samantha Oates at University of Birmingham <samantha.oates@alumni.ucl.ac.uk> S. R. Oates (Lancaster U.) reports on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of GRB 240715A 36 ks after the Fermi/GBM trigger (Fermi GBM team, GCN Circ. 36866). The UVOT exposures include the positions of XRT sources 1 and 2, but XRT source 3 is outside of the UVOT field of view (D'Elia et al., GCN 36890). In the UVOT exposures, optical sources are found consistent with XRT source 1 and 2. These sources are also observed in the DSS. Preliminary magnitudes using the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the two XRT sources are: Source Filter T_start(s) T_stop(s) Exp(s) Mag XRT source 1 white 36242 54326 4613 20.1+\-0.1 XRT source 2 white 36242 54326 4613 21.8+\-0.2 The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.01 in the direction of the burst (Schlegel et al. 1998). View this GCN Circular online at https://gcn.nasa.gov/circulars/36891. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...