{
  "bibcode": "2010GCN.10526....1G",
  "body": "J. M. Gelbord (PSU), S. D. Barthelmy (GSFC),\nW. H. Baumgartner (GSFC/UMBC), D. N. Burrows (PSU),\nN. Gehrels (NASA/GSFC), D. Grupe (PSU),\nS. T. Holland (CRESST/USRA/GSFC), J. A. Kennea (PSU),\nF. E. Marshall (NASA/GSFC), P. T. O'Brien (U Leicester),\nJ. P. Osborne (U Leicester), D. M. Palmer (LANL),\nP. Romano (INAF-IASFPA), T. Sakamoto (NASA/UMBC), M. H. Siegel (PSU),\nM. Stamatikos (OSU/NASA/GSFC), M. A. Stark (PSU),\nE. Troja (NASA/GSFC/ORAU) and T. N. Ukwatta (GSFC/GWU) report on\nbehalf of the Swift Team:\n\nAt 18:34:50 UT, the Swift Burst Alert Telescope (BAT) triggered and\nlocated GRB 100319A (trigger=416485).  Swift slewed immediately to the burst. \nThe BAT on-board calculated location is \nRA, Dec 278.442, -8.537 which is \n   RA(J2000)  =  18h 33m 46s\n   Dec(J2000) = -08d 32' 13\"\nwith an uncertainty of 3 arcmin (radius, 90% containment, including \nsystematic uncertainty).  The BAT light curve shows a single spike\nstructure with a duration of about 0.2 sec.  The peak count rate\nwas ~5000 counts/sec (15-350 keV), at ~0.0 sec after the trigger. \n\nThe XRT began observing the field at 18:35:57.2 UT, 66.6 seconds after\nthe BAT trigger. In promptly downlinked data we detect a low\nsignificance uncatalogued source at the following location (RA, Dec) = \n(278.43458, -8.51822), which is equivalent to:\n   RA(J2000)  =  18h 33m 44.3s,\n   Dec(J2000) = -08d 31m 05.6s,\nwith an uncertainty of 6.7 arcseconds (90% radius). This source lies 73 arcsecs\nfrom the BAT position. We await further downlinked data to confirm if this source\nis real. \n\nUVOT took a finding chart exposure of 150 seconds with the White filter\nstarting 70 seconds after the BAT trigger. No credible afterglow candidate has\nbeen found in the initial data products. The 2.7'x2.7' sub-image covers 25% of\nthe BAT error circle. The typical 3-sigma upper limit has been about 19.6 mag. \nThe 8'x8' region for the list of sources generated on-board covers 100% of the\nBAT error circle. The list of sources is typically complete to about 18 mag. No\ncorrection has been made for the large, but uncertain extinction expected. \n\nGiven the proximity of this burst to the Galactic Plane (0.01 degrees),\nthe shortness of the burst (16 ms trigger time) and soft emission\n(with no visible emission seen above 100 keV), this burst may be\nfrom an unknown Soft Gamma Repeater.  We note that this is 23 arcmin\nfrom the center of the W41 supernova remnant in a region with several\nknown pulsars. \n\nBurst Advocate for this burst is J. M. Gelbord (jgelbord AT astro.psu.edu). \nPlease contact the BA by email if you require additional information\nregarding Swift followup of this burst. In extremely urgent cases, after\ntrying the Burst Advocate, you can contact the Swift PI by phone (see\nSwift TOO web site for information: http://www.swift.psu.edu/too.html.)",
  "circularId": 10526,
  "createdOn": 1269025559000,
  "email": "scott@lheamail.gsfc.nasa.gov",
  "subject": "GRB 100319A: Swift detection of a burst; possible SGR",
  "submitter": "Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>",
  "eventId": "GRB 100319A"
}