{
  "bibcode": "2013GCN.15316....1S",
  "body": "M. Stamatikos (OSU), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC),\nJ. R. Cummings (GSFC/UMBC), E. E. Fenimore (LANL), N. Gehrels (GSFC),\nL. M. Z. Hagen (PSU), H. A. Krimm (GSFC/USRA), A. Y. Lien (NASA/GSFC/ORAU),\nC. B. Markwardt (GSFC), J. Norris (BSU), D. M. Palmer (LANL),\nT. Sakamoto (AGU), G. Sato (ISAS), J. Tueller (GSFC),\nT. N. Ukwatta (MSU) (i.e. the Swift-BAT team):\n\nUsing the data set from T30 to T+62 sec from the recent telemetry downlink,\nwe report further analysis of BAT GRB 131004A (trigger #573190)\n(Hagen, et al., GCN Circ. 15303).  The BAT ground-calculated position is\nRA, Dec = 296.108, -2.952 deg which is\n  RA(J2000)  =  19h 44m 26.0s\n  Dec(J2000) = -02d 57' 05.6\"\nwith an uncertainty of 1.1 arcmin, (radius, sys+stat, 90% containment).\nThe partial coding was 73%.\n\nThe mask-weighted light curve shows a single short spike starts at ~T-0.18,\npeaks at ~T0, and ends at ~T+1.35. T90 (15-350 keV) is 1.54 +- 0.33 sec\n(estimated error including systematics).\n\nThe time-averaged spectrum from T-0.25 to T+1.80 sec is best fit by a simple\npower-law model.  The power law index of the time-averaged spectrum is\n1.81 +- 0.11.  The fluence in the 15-150 keV band is 2.8 +- 0.2 x 10^-07 erg/cm2.\nThe 1-sec peak photon flux measured from T-0.27 sec in the 15-150 keV band\nis 3.4 +- 0.2 ph/cm2/sec.  All the quoted errors are at the 90% confidence\nlevel.\n\nThe burst spectrum appears at the softer end of short bursts, which have\nan average spectral index of 1.2 when fitting with a simple power-law model\n(Sakamoto et al. 2011). The spectral lag for this burst is 0.130 s +- 0.020 s\n(for the 50-100 keV and 15-25 keV bands), which is significantly longer\nthan those of regular short bursts.\n\nThe results of the batgrbproduct analysis are available at\nhttp://gcn.gsfc.nasa.gov/notices_s/573190/BA/",
  "circularId": 15316,
  "createdOn": 1381032583000,
  "email": "amy.y.lien@nasa.gov",
  "subject": "GRB 131004A, Swift-BAT refined analysis",
  "submitter": "Amy Lien at GSFC  <amy.y.lien@nasa.gov>",
  "eventId": "GRB 131004A"
}