{
  "bibcode": "2006GCN..5064....1S",
  "body": "G. Sato (ISAS), L. Barbier (GSFC), S. Barthelmy (GSFC),\nJ. Cummings (GSFC/ORAU), E. Fenimore (LANL), N. Gehrels (GSFC),\nD. Hullinger (BYU-Idaho), H. Krimm (GSFC/USRA), M. Koss (UMD),\nC. Markwardt (GSFC/UMD), J. Norris (GSFC), D. Palmer (LANL),\nA. Parsons (GSFC), T. Sakamoto (GSFC/ORAU), M. Stamatikos (GSFC/ORAU),\nE. Troja (INAF-IASFPA), J. Tueller (GSFC)\non behalf of the Swift-BAT team:\n\nUsing the data set from T-119 to T+183 sec from the recent telemetry downlink,\nwe report further analysis of BAT GRB 060502B (trigger #208275)\n(Troja, et al., GCN 5055).  The BAT ground-calculated position is RA,Dec =\n278.949, 52.642 deg {18h 35m 47.7s, 52d 38' 32.5\"} (J2000) +- 1.8 arcmin,\n(radius, sys+stat, 90% containment).  The partial coding was 92%.\n \nThe lightcurve consists of two spikes.  The main peak starts at ~T-0.060\nand has a FWHM of ~40 msec.  Its rise is faster than the decay.\nThere is also a possible second peak (a precurrsor) starting at\nT-0.3 sec with a FWHM of ~100 msec and a significance of only ~4 sigma.\nT90 (15-350 keV) is 90 +- 20 msec (estimated error including systematics).\n\nThe lag analysis shows this burst to be cleanly in the short hard burst class\n(Norris and Bonnell, 2006, ApJ, accepted; see, Figure 3).\nSpecifically, the measured lags for the main peak are:\n   -4.0 ms +- 3.0 ms  (15-25 keV vs.  50-100 keV)\n   -0.2 ms +- 2.8 ms  (25-50 keV vs. 100-350 keV)\n \nThe time-averaged spectrum from T-0.05 to T+0.04 is best fit by a simple\npower-law model.  The power law index of the time-averaged spectrum is\n0.92 +- 0.23.  The fluence in the 15-150 keV band is\n4 +- 0.5 x 10^-8 erg/cm2.  The 1-sec peak photon flux measured\nfrom T-0.43 sec in the 15-150 keV band is 4.4 +- 0.6 ph/cm2/sec.\nAll the quoted errors are at the 90% confidence level.",
  "circularId": 5064,
  "createdOn": 1146630683000,
  "email": "Scott@lheamail.gsfc.nasa.gov",
  "subject": "GRB 060502B:  Refined analysis of the Swift-BAT short burst",
  "submitter": "Scott Barthelmy at NASA/GSFC  <Scott@lheamail.gsfc.nasa.gov>",
  "eventId": "GRB 060502B"
}