{
  "bibcode": "2007GCN..6954....1T",
  "body": "J. Tueller (GSFC), S. D. Barthelmy (GSFC), J. Cummings (GSFC/UMBC),\nE. Fenimore (LANL), N. Gehrels (GSFC), S. T. Holland (CRESST/USRA/GSFC),\nH. Krimm (GSFC/USRA), C. Markwardt (GSFC/UMD), J. Norris (U. Denver),\nD. Palmer (LANL), A. Parsons (GSFC), T. Sakamoto (GSFC/UMBC),\nG. Sato (GSFC/ISAS), M. Stamatikos (GSFC/ORAU), T. Ukwatta (GWU)\n(i.e. the Swift-BAT team):\n \nUsing the data set from T-239 to T+625 sec from recent telemetry downlinks,\nwe report further analysis of BAT GRB 071020 (trigger #294835)\n(Holland, et al., GCN Circ. 6949).  The BAT ground-calculated position is\nRA, Dec = 119.666, 32.857 deg, which is \n   RA(J2000)  = 07h 58m 39.9s \n   Dec(J2000) = 32d 51' 25\" \nwith an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment).\nThe partial coding was 90%.\n \nThe mask-weighted lightcurve shows at least 8 overlapping pulses in the initial\nburst.  They all have approximately the same peak flux values.  This emission\nstarts at ~T-3 sec, peaks at ~T-1.5 sec, and ends at ~T+0.9 sec.\nT90 (15-350 keV) is 4.2 +- 0.2 sec (estimated error including systematics).\n\nThe spectral lag for this burst is:\n59 +7-9 msec for the 150-300 to 25-50 keV bands, and\n10 +8-7 msec for the 50-100 to 15-25 keV bands.\n \nThe time-averaged spectrum from T-3.0 to T+7.4 sec is best fit by a simple\npower-law model.  The power law index of the time-averaged spectrum is\n1.11 +- 0.05.  The fluence in the 15-150 keV band is 2.3 +- 0.1 x 10^-6 erg/cm2.\nThe 1-sec peak photon flux measured from T-0.36 sec in the 15-150 keV band\nis 8.4 +- 0.3 ph/cm2/sec.  All the quoted errors are at the 90% confidence\nlevel.\n\nFolding in the borderline results of the T90, the hardness ratio,\nthe spectral lag, and very marginal detection of extended emission in the lightcurve;\nwe think this is a Long burst, but we can not rule out the possibility\nof a SHB classification.",
  "circularId": 6954,
  "createdOn": 1192898803000,
  "email": "scott@lheamail.gsfc.nasa.gov",
  "subject": "GRB 071020, Swift-BAT refined analysis",
  "submitter": "Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>",
  "eventId": "GRB 071020"
}