{
  "bibcode": "2025GCN.40487....1S",
  "subject": "GRB 250516A: Swift-BAT refined analysis",
  "body": "T. Sakamoto (AGU), S. D. Barthelmy (GSFC), A. P. Beardmore (U Leicester),\nR. Gupta (GSFC), H. A. Krimm (NSF), S. Laha (GSFC/UMBC), A. Y. Lien (U\nTampa), C. B. Markwardt (GSFC), M. J. Moss (GSFC), D. M. Palmer (LANL), T.\nParsotan (GSFC), D. Sadaula (GSFC/UMBC), (i.e. the Swift-BAT team):\n\nUsing the data set from T-240 to T+963 sec from the recent telemetry\ndownlink, we report further analysis of BAT GRB 250516A (trigger #1314210)\n(Beardmore et al., GCN Circ. 40467).  The BAT ground-calculated position is\nRA, Dec = 334.612, -9.120 deg which is\n   RA(J2000)  =  22h 18m 26.8s\n   Dec(J2000) = -09d 07' 11.9\"\nwith an uncertainty of 1.1 arcmin, (radius, sys+stat, 90% containment).\nThe partial coding was 61%.\n\nThe mask-weighted light curve shows a multi-peaked structure that starts at\n~T-20 s and ends at ~T+23 s. The highest peak occurs at ~T+20 s. T90\n(15-350 keV) is 30.04 +- 6.01 sec (estimated error including systematics).\n\nThe time-averaged spectrum from T-19.96 to T+22.70 sec is best fit by a\nsimple power-law model.  The power law index of the time-averaged spectrum\nis 1.69 +- 0.08.  The fluence in the 15-150 keV band is 2.3 +- 0.1 x 10^-06\nerg/cm2. The 1-sec peak photon flux measured from T+19.39 sec in the 15-150\nkeV band is 3.8 +- 0.3 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/1314210\n",
  "submittedHow": "email",
  "submitter": "Amy <yarleen@gmail.com>",
  "circularId": 40487,
  "createdOn": 1747623875918,
  "eventId": "GRB 250516A"
}