{
  "bibcode": "2012GCN.13949....1C",
  "body": "GRB 121031A, Early peak observed with Swift-BAT\n  \nJ. R. Cummings (GSFC/UMBC), S. D. Barthelmy (GSFC),\nW. H. Baumgartner (GSFC/UMBC), E. E. Fenimore (LANL), N. Gehrels (GSFC),\nH. A. Krimm (GSFC/USRA), C. B. Markwardt (GSFC/UMD), D. M. Palmer (LANL),\nA. M. Parsons (GSFC), T. Sakamoto (GSFC/UMBC), G. Sato (ISAS),\nM. Stamatikos (GSFC/ORAU), J. Tueller (GSFC), T. N. Ukwatta (GWU)\n(i.e. the Swift-BAT team):\n\n\nWith an additional data set from T-240 to T-61 sec, we report further\nanalysis of BAT GRB 121031 (trigger #537195) (D'Elia, et al., GCN Circ.\n13934).  In an earlier circular (Barthelmy, et al., GCN Circ. 13936) we\ndescribed the second of two equal-sized peaks from this burst.  BAT\ntriggered on that second peak.  The earlier peak occurred during a pre-\nplanned slew maneuver, and its time interval was not covered by the data\navailable at the time the circular was produced.\n\nThe entire burst had two large peaks at T-190 and T0 that were about the\nsame in flux, duration, and shape.  Each was a FRED about 60 seconds long as\nseen in BAT.  There was a small peak at T-50 sec of about 5 seconds duration.\nFor the entire burst, T90 (15-350 keV) was 226 +- 19 sec (estimated error\nincluding systematics).\n  \nThe time-averaged spectrum from T-209.0 to T+98.3 sec is best fit by a\nsimple power-law model.  The power law index of the time-averaged spectrum\nis 1.50 +- 0.05.  The fluence in the 15-150 keV band is\n7.8 +- 0.2 x 10^-06 erg/cm2.  The 1-sec peak photon flux measured from\nT-190.72 sec in the 15-150 keV band is 2.4 +- 0.2 ph/cm2/sec.  All the\nquoted errors are at the 90% confidence level.",
  "circularId": 13949,
  "createdOn": 1351908363000,
  "email": "james.r.cummings@nasa.gov",
  "subject": "GRB 121031A, Early peak observed with Swift-BAT",
  "submitter": "Jay R. Cummings at NASA/GSFC/Swift  <james.r.cummings@nasa.gov>",
  "eventId": "GRB 121031A"
}