{
  "bibcode": "2007GCN..6966....1B",
  "body": "L. Barbier (GSFC), S. D. Barthelmy (GSFC), J. Cummings (GSFC/UMBC),\nE. Fenimore (LANL), N. Gehrels (GSFC), H. Krimm (GSFC/USRA),\nC. Markwardt (GSFC/UMD), D. Palmer (LANL), A. Parsons (GSFC),\nT. Sakamoto (GSFC/UMBC), G. Sato (GSFC/ISAS), M. Stamatikos (GSFC/ORAU),\nJ. Tueller (GSFC), T. Ukwatta (GWU)\n(i.e. the Swift-BAT team):\n \nUsing the data set from T-239 to T+472 sec from recent telemetry downlinks,\nwe report further analysis of BAT GRB 071021 (trigger #294974)\n(Sakamoto, et al., GCN Circ. 6958).  The BAT ground-calculated position is\nRA, Dec = 340.573, 23.764 deg, which is \n   RA(J2000)  = 22h 42m 17.6s \n   Dec(J2000) = 23d 45' 49\" \nwith an uncertainty of 3.4 arcmin, (radius, sys+stat, 90% containment).\nThe partial coding was 78%.\n \nThe mask-weighted light curve shows a slow rise starting at ~T-30 sec and\npeaking around T+85 sec.  The remaining portion of the lightcurve is\nconsistant with either a low-level constant emission out to ~T+225 sec or\nwith a decline to background around T+150 sec and then another weak peak\nfrom ~T+180 to ~T+220 sec.  This latter interpretation is consistant with a\nsmall flare in the XRT afterglow lightcurve around T+220 sec.\nT90 (15-350 keV) is 225 +- 10 sec (estimated error including systematics).\n \nThe time-averaged spectrum from T-31.4 to T+252.2 sec is best fit by a simple\npower-law model.  The power law index of the time-averaged spectrum is\n1.70 +- 0.21.  The fluence in the 15-150 keV band is 1.3 +- 0.2 x 10^-6 erg/cm2.\nThe 1-sec peak photon flux measured from T+87.32 sec in the 15-150 keV band\nis 0.7 +- 0.1 ph/cm2/sec.  All the quoted errors are at the 90% confidence\nlevel. \n\nThis burst has several characteristics which are typical of high\nredshift bursts.  Its duration is long (T90 = 225 sec) with relatively\nfew (two) significant peaks.  The 1-s peak flux is < 1.0 ph/cm2/s\nand the power-law photon index (1.70) is < 2.",
  "circularId": 6966,
  "createdOn": 1192995184000,
  "email": "scott@lheamail.gsfc.nasa.gov",
  "subject": "GRB 071021, Swift-BAT refined analysis",
  "submitter": "Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>",
  "eventId": "GRB 071021"
}