{
  "bibcode": "2013GCN.15163....1B",
  "body": "W. H. Baumgartner (GSFC/UMBC), S. D. Barthelmy (GSFC),\nJ. R. Cummings (GSFC/UMBC), E. E. Fenimore (LANL),\nN. Gehrels (GSFC), H. A. Krimm (GSFC/USRA),\nA. Y. Lien (NASA/GSFC/ORAU), D. Malesani (DARK/NBI),\nC. B. Markwardt (GSFC), D. M. Palmer (LANL),\nT. Sakamoto (AGU), G. Sato (ISAS), M. Stamatikos (OSU),\nJ. Tueller (GSFC), T. N. Ukwatta (MSU)\n(i.e. the Swift-BAT team):\n\nUsing the data set from T-240 to T+902 sec from the\nrecent telemetry downlink, we report further analysis\nof BAT GRB 130831B (trigger #568855) (Malesani, et al.,\nGCN Circ. 15141). The BAT ground-calculated position is\nRA, Dec = 192.454, -29.187 deg which is\n   RA(J2000)  =  12h 49m 48.9s\n   Dec(J2000) = -29d 11' 13.5\"\nwith an uncertainty of 2.1 arcmin, (radius, sys+stat,\n90% containment). The partial coding was 14%.\n\nBAT mask-weighted light curve shows a multi peak\nepisode starting from ~T-12 sec highest peak\naround T+1 sec and ending at ~T+30 sec.\nT90 (15-350 keV) is 37.8 +- 10.4 sec\n(estimated error including systematics).\n\nThe time-averaged spectrum from T-13.9 to T+30.6 sec\nis best fit by a simple power-law model.  The power\nlaw index of the time-averaged spectrum is 1.88 +- 0.21.\nThe fluence in the 15-150 keV band is\n1.4 +- 0.2 x 10^-06 erg/cm2. The 1-sec peak photon\nflux measured from T-0.05 sec in the 15-150 keV band\nis 2.4 +- 0.5 ph/cm2/sec.  All the quoted errors are\nat the 90% confidence level.\n\nThe results of the batgrbproduct analysis are available at\nhttp://gcn.gsfc.nasa.gov/notices_s/568855/BA/",
  "circularId": 15163,
  "createdOn": 1378072289000,
  "email": "tilan.ukwatta@gmail.com",
  "subject": "GRB 130831B, Swift-BAT refined analysis",
  "submitter": "Tilan Ukwatta at MSU  <tilan.ukwatta@gmail.com>",
  "eventId": "GRB 130831B"
}