{
  "bibcode": "2013GCN.15621....1D",
  "body": "M. De Pasquale (UCL-MSSL) and S. R. Oates (UCL-MSSL)\nreport on behalf of the Swift/UVOT team:\n\nThe Swift/UVOT began settled observations of the field of GRB 131227A\n66 s after the BAT trigger (Oates et al. GCN Circ. 15616).\nNo optical afterglow consistent with the enhanced XRT position\n(Evans et al. GCN Circ. 15618) or the source detected by KAIT (Zheng\net al. GCN 15617) 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            66          216          147         >20.6\nu_FC               278          528          246         >19.9\nwhite               66        13019         1430         >21.9\nv                  608         6785          471         >19.7\nb                  534        12318         1160         >21.1\nu                  278        11406         1366         >20.9\nw1                5558         7195          393         >20.1\nw2                4942         6580          393         >20.5\n\nThe magnitudes in the table are not corrected for the strong Galactic\nextinction due to the reddening of E(B-V) = 1.02 in the direction of\nthe burst (Schlegel et al. 1998).",
  "circularId": 15621,
  "createdOn": 1388159733000,
  "email": "m.depasquale@ucl.ac.uk",
  "subject": "GRB 131227A: Swift/UVOT Upper Limits",
  "submitter": "Massimiliano de Pasquale at MSSL-UCL  <m.depasquale@ucl.ac.uk>",
  "eventId": "GRB 131227A"
}