{
  "bibcode": "2013GCN.15168....1C",
  "body": "M. M. Chester (PSU) and L.M.Z. Hagen (PSU) report on behalf of the\nSwift/UVOT team:\n\nThe Swift/UVOT began settled observations of the field of GRB 130831A\n(Hagen et al., GCN Circ. 15139) 191 seconds after the BAT trigger.\nA source consistent with the enhanced XRT position (Evans et al.,\nGCN Circ. 15147) is detected in the initial UVOT exposures.\n\nPreliminary detections and 3-sigma upper limits using the UVOT\nphotometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373)\nfor the first finding chart (FC) exposures and subsequent exposures are:\n\nFilter         T_start(s)   T_stop(s)      Exp(s)           Mag\nv                498          818           58      14.4 +/- 0.1\nv              10802        11709          885      18.0 +/- 0.1\nv              46801        47000          196      > 18.9\n\nb               448           767           58      14.9 +/- 0.1\nb             23522         23925          393      19.2 +/- 0.2\nb             40193         41100          885      20.1 +/- 0.2\n\nu_FC            191            441         246      14.6 +/- 0.1\nu               572            742          39      13.9 +/- 0.1\nu             16594          23517        1645      18.3 +/- 0.1\n\nw1              548            849          40      13.9 +/- 0.1\nw1            15688          16588         886      18.1 +/- 0.1\n\nm2              673            843          39      13.6 +/- 0.1\nm2            11714          12387         663      17.5 +/- 0.1\n\nw2              474            494          19      14.8 +/- 0.1\nw2             9896          10796         886      17.5 +/- 0.1\nw2            41107          46795        1009      19.3 +/- 0.2\n\nThe magnitudes in the table are not corrected for the Galactic\nextinction due to the reddening of E(B-V) = 0.04 in the direction\nof the burst (Schlegel et al. 1998).",
  "circularId": 15168,
  "createdOn": 1378131471000,
  "email": "chester@astro.psu.edu",
  "subject": "GRB 130831A:  Swift/UVOT Observations",
  "submitter": "Margaret Chester at PSU  <chester@astro.psu.edu>",
  "eventId": "GRB 130831A"
}