{
  "eventId": "GRB 250615A",
  "circularId": 40747,
  "submitter": "Paul Kuin at MSSL <npkuin@gmail.com>",
  "subject": "GRB 250615A: Swift/UVOT Upper Limits",
  "body": "N.P.M.Kuin (UCL/MSSL) and S. Dichiara (PSU) report on behalf of the\nSwift/UVOT team:\n\nThe Swift/UVOT began settled observations of the field of GRB 250615A\n152 s after the BAT trigger (Dichiara et al., GCN Circ. 40736).\nNo optical afterglow consistent with the enhanced XRT position (Goad et\nal., GCN Circ. 40739) is detected in the initial UVOT exposures.\nPreliminary 3-sigma upper limits using the UVOT photometric system\n(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first\nfinding chart (FC) exposure and subsequent exposures are:\n\nFilter         T_start(s)   T_stop(s)      Exp(s)         Mag\n\nu_FC               152          402          246         >19.8\nwhite              432         1722          284         >21.0\nv                  483         1772          156         >19.5\nb                  408         1697          136         >20.7\nu                  152         1672          363         >20.0\nw1                 532         1821          136         >19.5\nw2                 804         1747           78         >19.2\n\nThe magnitudes in the table are not corrected for the Galactic extinction\ndue to the reddening of E(B-V) = 1.165 in the direction of the burst\n(Schlegel et al. 1998).\n",
  "createdOn": 1750073915730,
  "submittedHow": "email",
  "bibcode": "2025GCN.40747....1K"
}