{
  "bibcode": "2012GCN.13317....1K",
  "body": "H. A. Krimm (GSFC/USRA), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC),\nJ. R. Cummings (GSFC/UMBC), E. E. Fenimore (LANL), N. Gehrels (GSFC),\nC. B. Markwardt (GSFC), D. M. Palmer (LANL), T. Sakamoto (GSFC/UMBC),\nG. Sato (ISAS), M. Stamatikos (OSU), J. Tueller (GSFC), T. N. Ukwatta (MSU)\n(i.e. the Swift-BAT team):\n \nUsing the data set from T-60 to T+243 sec from recent telemetry downlinks,\nwe report further analysis of BAT GRB 120521B (trigger #522586)\n(Cummngs, et al., GCN Circ. 13305).  The BAT ground-calculated position is\nRA, Dec = 197.016, -52.742 deg, which is \n   RA(J2000)  =  13h 08m 03.9s \n   Dec(J2000) = -52d 44' 31.9\" \nwith an uncertainty of 1.6 arcmin, (radius, sys+stat, 90% containment).\nThe partial coding was 35%.\n \nThe mask-weighted light curve shows several overlapping peaks starting\nat ~T-1 sec, with equal-amplitude maximum peaks at ~T+6 and ~T+32 sec,\nand ending at around T+180 sec.  There is a possibility (at the 2-sigma level)\nthat emission continues out past the T+243sec end of the downlinked data.\nT90 (15-350 keV) is 31.4 +- 4.0 sec (estimated error including systematics).\n \nThe time-averaged spectrum from T-1.39 to T+35.58 sec is best fit by a simple\npower-law model.  The power law index of the time-averaged spectrum is\n0.97 +- 0.15.  The fluence in the 15-150 keV band is 1.5 +- 0.1 x 10^-6 erg/cm2.\nThe 1-sec peak photon flux measured from T+31.04 sec in the 15-150 keV band\nis 0.9 +- 0.2 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/522586/BA/",
  "circularId": 13317,
  "createdOn": 1337640535000,
  "email": "scott@lheamail.gsfc.nasa.gov",
  "subject": "GRB 120521B: Swift-BAT refined analysis",
  "submitter": "Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>",
  "eventId": "GRB 120521B"
}