{
  "bibcode": "2005GCN..4397....1B",
  "body": "L. Barbier (GSFC), S. Barthelmy (GSFC), A. Beardmore (U Leicester),\nD. Burrows (PSU), J. Cummings (GSFC/NRC), A. Falcone (PSU), N. Gehrels (GSFC),\nK. Page (U Leicester), A. Retter (PSU), P. Roming (PSU),\nT. Sakamoto (GSFC)\non behalf of the Swift team:\n\nAt 18:07:16 UT, Swift-BAT triggered and located GRB 051227 (trigger=174738).\nThe spacecraft slewed immediately.  The BAT on-board calculated location is\nRA,Dec 125.270d,+31.929d {08h 21m 05s,+31d 55' 44\"} (J2000), with an uncertainty\nof 3 arcmin (radius, 90% containment, stat+sys).  The BAT light curve shows\na multi-peak structure with a total duration of at least 8 sec.  The peak count\nrate was ~3500 counts/sec (15-350 keV), at 0 seconds after the trigger.\n\nThe XRT began observing the GRB at 18:08:49 UT, 93s after the BAT trigger.\nA bright fading uncataloged source was found by the on-board centroiding\nalgorithm at:\n RA(J2000)=  08h 20m 57.6s\nDEC(J2000)= +31d 55' 33.5\"\nwith an uncertainty of 7 arcseconds radius (90% containment).  This position\nhas not been corrected for the XRT boresight and retains a 4-5 arcsecond\nresidual systematic error, which is included in the 7 arcsecond error radius.\nThis position lies 95 arcseconds from the centre of the BAT error circle.\nThe initial X-ray flux is estimated to be 1.1e-9 erg/cm2/sec (0.2-10keV).\n\nUVOT took a finding chart exposure of nominal 200 seconds with the V filter\nstarting 96 seconds after the BAT trigger.  No afterglow candidate\nhas been found in the initial data products.  Image catalog data are not\navailable at this time.  The overlap of the 8'x8' region for the list\nof sources generated on-board and the XRT error circle is uncertain.\nNo correction has been made for the expected visual extinction\nof about 0.1 magnitudes.\n\nWe note that according to SIMBAD, there is a galactic cluster NSC J082047+315700\nwithin 2.7 arcmin from this location, but this is definitely a long burst\n(not a short GRB).",
  "circularId": 4397,
  "createdOn": 1135709987000,
  "email": "Scott@lheamail.gsfc.nasa.gov",
  "subject": "GRB 051227: Swift detection of a burst",
  "submitter": "Scott Barthelmy at NASA/GSFC  <Scott@lheamail.gsfc.nasa.gov>",
  "eventId": "GRB 051227"
}