{
  "bibcode": "2009GCN..9443....1P",
  "body": "D. M. Palmer (LANL), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC),\nJ. K. Cannizzo (NASA/UMBC), J. R. Cummings (GSFC/UMBC), E. E. Fenimore (LANL),\nN. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), C. B. Markwardt (GSFC/UMD),\nT. Sakamoto (GSFC/UMBC), G. Sato (ISAS), M. Stamatikos (GSFC/ORAU),\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 090530 (trigger #353567)\n(Cannizzo, et al., GCN Circ. 9438).  The BAT ground-calculated position is\nRA, Dec = 179.400, 26.590 deg, which is \n   RA(J2000)  =  11h 57m 36.0s \n   Dec(J2000) = +26d 35' 23.0\" \nwith an uncertainty of 1.9 arcmin, (radius, sys+stat, 90% containment).\nThe partial coding was 41%.\n \nThe mask-weighted light curve shows a FRED-like peak starting at ~T-0.3 sec,\npeaking at ~T+0.2 sec, and returning almost to background.  Then a second and\nmuch smaller peak starts at ~T+35 sec, peaks at ~T+45 sec, and ends\nat ~T+50 sec.  There is an ~3-sigma precursor peak at T-4sec.  T90 (15-350 keV)\nis 48 +- 36 sec (estimated error including systematics).\n \nThe time-averaged spectrum from T-12.2 to T+51.8 sec is best fit by a simple\npower-law model.  The power law index of the time-averaged spectrum is\n1.61 +- 0.17.  The fluence in the 15-150 keV band is 1.1 +- 0.1 x 10^-6 erg/cm2.\nThe 1-sec peak photon flux measured from T+0.0 sec in the 15-150 keV band\nis 2.5 +- 0.3 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/353567/BA/",
  "circularId": 9443,
  "createdOn": 1243686847000,
  "email": "scott@lheamail.gsfc.nasa.gov",
  "subject": "GRB 090530: Swift-BAT refined analysis",
  "submitter": "Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>",
  "eventId": "GRB 090530"
}