{
  "circularId": 45686,
  "subject": "GRB 260921A: Swift-BAT refined analysis",
  "eventId": "GRB 260921A",
  "body": "T. Parsotan (GSFC), S. D. Barthelmy (GSFC), R. Gupta (GSFC), H. A. Krimm\n(NSF), S. Laha (GSFC/UMBC), A. Y. Lien (U Tampa), C. B. Markwardt (GSFC),\nM. J. Moss (GSFC), K. L. Page (U Leicester), D. M. Palmer (LANL), D.\nSadaula (GSFC/UMBC), T. Sakamoto (AGU) (i.e. the Swift-BAT team):\n\nUsing the data set from T-61 to T+243 sec from the recent telemetry\ndownlink, we report further analysis of BAT GRB 260921A (trigger #1512356)\n(Page et al., GCN Circ. 45676).  The BAT ground-calculated position is\nRA, Dec = 145.376, 2.849 deg which is\n   RA(J2000)  =  09h 41m 30.2s\n   Dec(J2000) = +02d 50' 55.6\"\nwith an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment).\nThe partial coding was 27%.\n\nThe mask-weighted light curve shows a single-pulse structure that starts at\n~T-7 s, peaks at ~T0, and ends at ~T+7 s. T90 (15-350 keV) is 8.62 +- 1.44\nsec (estimated error including systematics).\n\nThe time-averaged spectrum from T-6.88 to T+6.93 sec is best fit by a\nsimple power-law model.  The power law index of the time-averaged spectrum\nis 1.29 +- 0.07.  The fluence in the 15-150 keV band is 3.4 +- 0.1 x 10^-06\nerg/cm2. The 1-sec peak photon flux measured from T+0.13 sec in the 15-150\nkeV band is 7.5 +- 0.6 ph/cm2/sec.  All the quoted errors are at the 90%\nconfidence level.\n\nThe results of the batgrbproduct analysis are available at\nhttps://swift.gsfc.nasa.gov/results/batgrbcat/BAT_refined_circular/1512356\n",
  "createdOn": 1790042287917,
  "submitter": "Amy <yarleen@gmail.com>",
  "submittedHow": "email"
}