{
  "bibcode": "2005GCN..3645....1V",
  "body": "S. Vaughan, A. Beardmore, M. Goad, O. Godet, J. Osborne, K. Page (U. Leicester),\nS. Barthelmy (GSFC), D. Burrows (PSU), J. Cummings (GSFC/NRC), N. Gehrels (GSFC),\nJ. Kennea (PSU), H. Krimm (GSFC/USRA), D. Palmer (LANL), A. Blustin (MSSL),\nS. Holland (GSFC/USRA), M. De Pasquale (MSSL)\non behalf of the Swift team:\n\nAt 13:58:52.85 UT, the Swift-BAT instrument triggered (trigger=146731)\non a weak event.  Using only the TDRSS lightcurve data we can not confirm\nor reject that this is a real GRB.  If it is a real GRB, then it might \nbe a short GRB.  There was a single spike of duration less than 128 msec\nin the 100-350 keV band, and no apparent emission in the lower energy bands.\nThe BAT trigger duration was 32 msec which is consistent, but not definitive,\nwith the short nature of this event.  The rate data currently available\nis also consistent with a cosmic ray event interacting in the instrument\nor spacecraft and showering the BAT detector.  Such events do not produce\na point source in the image, so if that were the case, the 6.24 sigma peak\ndetection in the image would be an unlikely, but still feasible,\nstatistical deviation.  The on-board calculated position\nis 213.420d,+9.444 {+14h 13m 41s, +09d 26' 38\"}  (J2000) +- 3arcmin\n(radius, 90%, sys+stat).  We will know more about this event when\nthe full data set arrives in a couple hours.\n\nThe XRT began observing the burst at 14:00:04 UT, 71 seconds after\nthe BAT trigger.  No source was found by the on board software due to\nlow flux.  The full field XRT lightcurve does not show any significant\nenhancement over background, and ground processing will be necessary\nto determine if a faint afterglow is detected.\n\nThe Swift Ultra Violet/Optical Telescope (UVOT) observations began\nat 14:00:02 (69 seconds after the BAT trigger).  The first data taken\nafter the spacecraft settled was a 100 sec exposure using the V filter\nwith the midpoint of the observation at 119 sec after the BAT trigger.\nBased on comparison with the DSS, we detect no new source within\nthe Genie image down to a 5 sigma upper limit magnitude of V=18.3.",
  "circularId": 3645,
  "createdOn": 1121784881000,
  "email": "Scott@lheamail.gsfc.nasa.gov",
  "subject": "Swift-BAT detection of a possible GRB",
  "submitter": "Scott Barthelmy at NASA/GSFC  <Scott@lheamail.gsfc.nasa.gov>"
}