{
  "bibcode": "2008GCN..7772....1P",
  "body": "D. Palmer (LANL), S. D. Barthelmy (GSFC), W. Baumgartner (GSFC/UMBC),\nJ. Cummings (GSFC/UMBC), E. Fenimore (LANL), N. Gehrels (GSFC),\nH. Krimm (GSFC/USRA), C. Markwardt (GSFC/UMD), K. McLean (GSFC/UMD),\nT. Sakamoto (GSFC/UMBC), G. Sato (GSFC/ISAS), M. Stamatikos (GSFC/ORAU),\nM. C. Stroh (PSU), J. Tueller (GSFC), T. Ukwatta (GWU)\n(i.e. the Swift-BAT team):\n \nUsing the data set from T-239 to T+963 sec from recent telemetry downlinks,\nwe report further analysis of BAT GRB 080523 (trigger #312242)\n(Stroh, et al., GCN Circ. 7767).  The BAT ground-calculated position is\nRA, Dec = 20.769, -64.060 deg, which is \n   RA(J2000)  =  01h 23m 04.4s \n   Dec(J2000) = -64d 03' 36.0\" \nwith an uncertainty of 1.7 arcmin, (radius, sys+stat, 90% containment).\nThe partial coding was 100%.\n \nThe mask-weighted light curve shows a FRED-like peak starting at ~T-10 sec,\npeaking at ~T+4, and ending at ~T+80 sec.  There is a weak second peak\nstarting,ending at 80,110 sec, respectively.  T90 (15-350 keV) is\n102 +- 15 sec (estimated error including systematics).\n \nThe time-averaged spectrum from T-6.1 to T+111.9 sec is best fit by a simple\npower-law model.  The power law index of the time-averaged spectrum is\n1.65 +- 0.18.  The fluence in the 15-150 keV band is 8.8 +- 1.0 x 10^-7 erg/cm2.\nThe 1-sec peak photon flux measured from T+3.89 sec in the 15-150 keV band\nis 0.5 +- 0.1 ph/cm2/sec.  All the quoted errors are at the 90% confidence\nlevel. \n \nThe results of the batgrbproduct analysis are available at\nhttp://gcn.gsfc.nasa.gov/notices_s/312242/BA/\n \nThis burst satisfies Sakamoto/Ukwatta Swift-BAT possible high-z criteria\n(Ukwatta et al. arXiv:0802.3815).\n1) Power Law photon index = 1.65     (PL photon index < 2)\n2) 1-s peak photon flux   = 0.51     (1-s peak photon flux < 1.0 ph/cm2/s)\n3) Light curve variance   = 1.2e-05  (Variance < 0.0001)\n4) T90/(Peak photon flux) = 201      (T90/(Peak photon flux) > 100)\nBased on a limited sample of bursts, these criteria yield an 85% chance\nit has a redshift greater than 3.5.",
  "circularId": 7772,
  "createdOn": 1211663810000,
  "email": "scott@lheamail.gsfc.nasa.gov",
  "subject": "GRB 080523, Swift-BAT refined analysis",
  "submitter": "Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>",
  "eventId": "GRB 080523"
}