{
  "bibcode": "2009GCN..9290....1S",
  "body": "M. Stamatikos (GSFC/ORAU), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC),\nJ. R. Cummings (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),\nJ. Tueller (GSFC), T. N. Ukwatta (GWU)\n(i.e. the Swift-BAT team):\n \nUsing the data set from T-60 to T+243 sec from the recent telemetry downlink,\nwe report further analysis of BAT GRB 090429B (trigger #350854)\n(Ukwatta, et al., GCN Circ. 9281).  The BAT ground-calculated position is\nRA, Dec = 210.672, 32.167 deg, which is \n   RA(J2000)  =  14h 02m 41.2s \n   Dec(J2000) = +32d 10' 02.0\" \nwith an uncertainty of 1.3 arcmin, (radius, sys+stat, 90% containment).\nThe partial coding was 84%.\n \nThe mask-weighted light curve shows a main peak starting at ~T-4 sec,\npeaking at ~T-0.1 sec, and ending around T+3 sec.  There are two very\nweak peaks: ~T+30 to ~T+70 sec, and ~T+100 to ~T+110 sec.\nT90 (15-350 keV) is 5.5 +- 1.0 sec (estimated error including systematics).\n \nThe time-averaged spectrum from T-4.5 to T+2.4 sec is best fit by a power law\nwith an exponential cutoff.  This fit gives a photon index 0.47 +- 0.77, \nand Epeak of 42.1 +- 5.6 keV (chi squared 29.6 for 56 d.o.f.).  For this\nmodel the total fluence in the 15-150 keV band is 3.1 +- 0.3 x 10^-7 erg/cm2\nand the 1-sec peak flux measured from T-0.28 sec in the 15-150 keV band is\n1.6 +- 0.2 ph/cm2/sec.  A fit to a simple power law gives a photon index\nof 1.96 +- 0.13 (chi squared 45.3 for 57 d.o.f.).  All the quoted errors\nare at the 90% confidence level. \n \nThe results of the batgrbproduct analysis are available at\nhttp://gcn.gsfc.nasa.gov/notices_s/350854/BA/",
  "circularId": 9290,
  "createdOn": 1241006975000,
  "email": "scott@lheamail.gsfc.nasa.gov",
  "subject": "GRB 090429B: Swift-BAT refined analysis",
  "submitter": "Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>",
  "eventId": "GRB 090429B"
}