{
  "bibcode": "2006GCN..4907....1P",
  "body": "D. Palmer (LANL), L. Barbier (GSFC), S. Barthelmy (GSFC),\nJ. Cummings (GSFC/NRC), E. Fenimore (LANL), N. Gehrels (GSFC),\nD. Hullinger (BYU-Idaho), H. Krimm (GSFC/USRA), C. Markwardt (GSFC/UMD), \nA. Parsons (GSFC), M. Perri (ASDC), T. Sakamoto (GSFC/NRC),\nG. Sato (ISAS), J. Tueller (GSFC)\non behalf of the Swift-BAT team:\n\nUsing the data set from T-239 to T+963 sec from recent telemetry downlinks,\nwe report further analysis of BAT GRB 060322 (trigger #202442)\n(Perri, et al., GCN 4903).  The BAT ground-calculated position is\nRA,Dec = 274.235,-36.721 deg {18h 16m 56.4s, -36d 43' 14.7\"} (J2000)\n+- 1.0 arcmin, (radius, sys+stat, 90% containment).  The partial coding was 80%.\n \nThe mask-weighted lightcurve shows two well separated episodes of emission.\nThe first episode starts at T-22 sec and ends at T+40 sec with six main peaks\nwithin that interval.  Then the emission drops below the BAT sensitivity\nuntil the second episode.  The second episode starts at T+155 sec and\nends at T+204 sec with six main peaks within that second interval.\nThere is no further emission out to T+670 sec.  T90 (15-350 keV) is\n213 +- 5 sec (estimated error including systematics).\n \nThe time-averaged spectrum from T-21.7 to T+232.3 is best fit by a power law\nwith an exponential cutoff.  This fit gives a photon index 1.04 +- 0.32, \nand Epeak of 94.4 +- 44.7 keV (chi squared 57.29 for 56 d.o.f.).  \nFor this model the total fluence in the 15-150 keV band is\n5.1 +- 0.2 x 10^-06 erg/cm2 and the 1-sec peak flux measured from T+182.19 sec\nin the 15-150 keV band is 2.1 +- 0.2 ph/cm2/sec.  A fit to a simple\npower law gives a photon index of 1.58 +- 0.07 (chi squared 65.5\nfor 57 d.o.f.).  All the quoted errors are at the 90% confidence level.\n\nAdditionally, separate spectral analyses of the two episodes\nin the light curve show that the second episode is spectrally softer\nthan the first.  The best fit to the first episode is a simple power law\nwith a photon index of 1.36 +- 0.09 (chi squared 30.3 for 56 d.o.f.).\nThe second episode is best fit by a power law with an exponential\ncutoff.  This fit gives a photon index alpha = 0.89 +-0.31 and Epeak \nof 72.8 +- 12.6 keV (chi squared 51.6 for 55 d.o.f.).  Fitting a\nsimple power law to the second episode yields a power-law index\nof 1.69 +- 0.07 (chi squared 70.5 for 56 d.o.f.)  All the quoted errors\nare at the 90% confidence level.",
  "circularId": 4907,
  "createdOn": 1143146037000,
  "email": "Scott@lheamail.gsfc.nasa.gov",
  "subject": "GRB 060322:  Refined analysis of the Swift-BAT burst",
  "submitter": "Scott Barthelmy at NASA/GSFC  <Scott@lheamail.gsfc.nasa.gov>",
  "eventId": "GRB 060322"
}