{
  "bibcode": "2006GCN..5590....1S",
  "body": "M. Stamatikos (NASA/ORAU), S. D. Barthelmy (GSFC),\nD. N. Burrows (PSU), M. Capalbi (ASDC), M.L. Conciatore (ASDC),\nN. Gehrels (NASA/GSFC), C. Guidorzi (Univ Bicocca&INAF-OAB),\nS. T. Holland (GSFC/USRA), J. A. Kennea (PSU),\nC. B. Markwardt (GSFC/UMD), D. M. Palmer (LANL), M. Perri (ASDC),\nT. Sakamoto (NASA/ORAU), D. E. Vanden Berk (PSU) and\nH. Ziaeepour (UCL-MSSL) report on behalf of the Swift Team:\n\nAt 11:38:06 UT, the Swift Burst Alert Telescope (BAT) triggered and\nlocated GRB 060923B (trigger=230702).  Swift slewed immediately to the burst. \nThe BAT on-board calculated location is \nRA,Dec 238.201, -30.907 {15h 52m 48s, -30d 54' 25\"} (J2000)\nwith an uncertainty of 3 arcmin (radius, 90% containment, including \nsystematic uncertainty).  The BAT light curve shows a single peak\nwith a duration of about 10 sec.  The peak count rate\nwas ~1500 counts/sec (15-350 keV), at ~4 sec after the trigger. \n\nThe XRT began observing the field at 11:40:00 UT, 114 seconds after\nthe BAT trigger. XRT centroided on a cosmic ray on-board, so the\nposition sent out in our first, automated XRT Position Notice is\nincorrect. From preliminary ground analysis of photon-counting mode\ndata, XRT did find an uncatalogued X-ray source located at RA(J2000)\n= 15h 52m 46.83s, Dec(J2000) = -30d 54' 12.6\", with an estimated\nuncertainty of 6.5 arcseconds (90% confidence radius). This position\nwas sent out via BACODINE in a second XRT Position Notice with the\ncorrect position. This location is 21 arcseconds from the BAT\non-board position, within the BAT error circle. The initial flux in\nthe 2.5s image was 2.4e-11 erg/cm2/s (0.2-10 keV). \n\nUVOT took a finding chart exposure of nominal 200 seconds with the\nWhite (160-650 nm) filter starting 122 seconds after the BAT trigger. \nNo afterglow candidate has been found in the initial data products. \nImage catalog data are not available at this time. The 8'x8' region\nfor the list of sources generated on-board covers 100% of the XRT\nerror circle. The list of sources is typically complete to about 18\nmag. The overlap of the sub-image and the XRT error circle is 100%. \nNo source is seen in the XRT error circle to a magnitude of\napproximately 18.5.  No correction has been made for the expected\nextinction corresponding to E(B-V) of 0.15.",
  "circularId": 5590,
  "createdOn": 1159012966000,
  "email": "scott@lheamail.gsfc.nasa.gov",
  "subject": "GRB 060923B: Swift detection of a burst",
  "submitter": "Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>",
  "eventId": "GRB 060923B"
}