{
  "bibcode": "2016GCN.19593....1D",
  "body": "M. De Pasquale (UCL-MSSL) and A. Maselli (INAF-IASFPA)\nreport on behalf of the Swift/UVOT team:\n\nThe Swift/UVOT began settled observations of the field of GRB 160625A\n7183 s after the BAT trigger (Maselli et al., GCN Circ. 19577).\nNo optical afterglow consistent with the XRT position\n(Burrows et al. GCN Circ. 19578) is detected in the UVOT exposures.\nWe note the presence of a source approximately 3'' from the\nXRT position. This source is present in the USNO catalogue.\nPreliminary 3-sigma upper limits using the UVOT photometric system\n(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the\nexposures are:\n\nFilter         T_start(s)   T_stop(s)      Exp(s)         Mag\n\nwhite             7183         7952          344         >20.8\nv                 8163         8363          197         >19.0\nb                 7548         7747          197         >19.9\nu                 7342         7542          197         >19.4\nm2                8368         8483          113         >18.9\nw2                7958         8158          197         >19.6\n\nThe magnitudes in the table are not corrected for the substantial Galactic\nextinction due to the reddening of E(B-V) = 1.51 in the direction of the\nburst (Schlegel et al. 1998).\n\n-- \n\nDr. Massimiliano De Pasquale\nResearch associate - Swift UVOT scientist\nMullard Space Science Laboratory, University College London",
  "circularId": 19593,
  "createdOn": 1466974112000,
  "email": "m.depasquale@ucl.ac.uk",
  "subject": "GRB 160625A: Swift/UVOT Upper Limits",
  "submitter": "Massimiliano de Pasquale at IASF-Palermo  <m.depasquale@ucl.ac.uk>",
  "eventId": "GRB 160625A"
}