{
  "bibcode": "2015GCN.18766....1B",
  "body": "A.A. Breeveld (UCL-MSSL), S.W.K. Emery (UCL-MSSL) and A.Y. Lien \n(GSFC/UMBC) report on behalf of the Swift/UVOT team:\n\nThe Swift/UVOT began settled observations of the field of GRB 151228B\n49 s after the BAT trigger (Lien et al., GCN Circ. 18739).\nA fading source consistent with the XRT position (Goad et al. GCN Circ. \n18743) is detected in the initial UVOT exposures in the white filter.\n\nThe preliminary UVOT position is:\n     RA  (J2000) =  22:57:41.87 = 344.42446 (deg.)\n     Dec (J2000) = +08:04:53.7  =   8.08159 (deg.)\nwith an estimated uncertainty of 0.58 arc sec. (radius, 90% confidence).\n\nPreliminary detections and 3-sigma upper limits using the UVOT \nphotometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for \nthe early exposures are:\n\nFilter         T_start(s)   T_stop(s)      Exp(s)           Mag\n\nwhite               70          220          147         19.62 �� 0.19\nv                   49         6132          306        >19.2\nb                  537         5514          274        >20.0\nu                  282         5309          520        >20.1\nw1                 661         6373          303        >20.1\nm2                6137         6337          197        >19.9\nw2                1386         5927          216        >20.8\n\nThe magnitudes in the table are not corrected for the Galactic \nextinction due to the reddening of E(B-V) = 0.06 in the direction of the \nburst (Schlegel et al. 1998).",
  "circularId": 18766,
  "createdOn": 1451461504000,
  "email": "a.breeveld@ucl.ac.uk",
  "subject": "GRB 151228B: Swift/UVOT Detection",
  "submitter": "Alice Breeveld at MSSL-UCL  <a.breeveld@ucl.ac.uk>",
  "eventId": "GRB 151228B"
}