{
  "body": "M. H. Siegel (PSU) and Ambrosi (INAF-IASFPA)\nreport on behalf of the Swift/UVOT team:\n\nThe Swift/UVOT began settled observations of the field of GRB 250805A\n3536 s after the BAT trigger (Ambrosi et al., GCN Circ. 41233).\nNo optical afterglow consistent with the XRT position (Beardmore et al., \nGCN Circ. 41238) or optical afterglow (Izzo et al., GCN Circ. 41241; Li et\nal., GCN Circ. 41241) 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\nwhite_FC          3536         3686          147         >21.3\nwhite             3536         4306          344         >21.7\nb                 3902         4101          197         >20.9\nu                 3696         3895          197         >20.6\nw2                4312         4460          146         >20.7\n\nThe magnitudes in the table are not corrected for the Galactic extinction\ndue to the reddening of E(B-V) = 0.092 in the direction of the burst\n(Schlegel et al. 1998).",
  "subject": "GRB 250805A: Swift/UVOT Upper Limits",
  "eventId": "GRB 250805A",
  "bibcode": "2025GCN.41265....1S",
  "submitter": "Mike Siegel at PSU/Swift MOC <mhs18@psu.edu>",
  "format": "text/plain",
  "submittedHow": "web",
  "createdOn": 1754570862680,
  "circularId": 41265
}