{
  "bibcode": "2017GCN.21141....1E",
  "body": "S.W.K. Emery (UCL-MSSL) and J.G. Gropp (PSU)\nreport on behalf of the Swift/UVOT team:\n\nThe Swift/UVOT began settled observations of the field of GRB 170524A\n67 s after the BAT trigger (Gropp et al., GCN Circ. 21135).\nNo optical afterglow consistent with the XRT position\n(Evans et al. GCN Circ. 21136)\nis 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            67          217          147         >20.4\nu_FC               280          529          246         >19.5\nwhite               67         1007          334         >20.6\nv                  610         1058           58         >17.9\nb                  535         1157           58         >18.7\nu                  280         1132          285         >19.5\nw1                 660         1107           58         >18.3\nm2                1063         1082           19         >17.3\nw2                 586         1033           58         >18.6\n\nThe magnitudes in the table are not corrected for the Galactic extinction\ndue to the reddening of E(B-V) = 2.82 in the direction of the burst\n(Schlegel et al. 1998).",
  "circularId": 21141,
  "createdOn": 1495715822000,
  "email": "samuel.emery.15@ucl.ac.uk",
  "subject": "GRB 170524A: Swift/UVOT Upper Limits",
  "submitter": "Sam Emery at MSSL-UCL  <samuel.emery.15@ucl.ac.uk>",
  "eventId": "GRB 170524A"
}