{
  "createdOn": 1743457092484,
  "subject": "GRB 250327A Swift-BAT refined analysis",
  "format": "text/plain",
  "bibcode": "2025GCN.39987....1B",
  "submitter": "Mike Moss at NASA GSFC <mikejmoss3@gmail.com>",
  "eventId": "GRB 250327A",
  "circularId": 39987,
  "submittedHow": "web",
  "body": "S. D. Barthelmy (GSFC), R. Gupta (GSFC),\nH. A. Krimm (NSF), S. Laha (GSFC/UMBC),\nA. Y. Lien (U Tampa), C. B. Markwardt (GSFC),\nM. J. Moss (GSFC), D. M. Palmer (LANL),\nT. Parsotan (GSFC), D. Sadaula (GSFC/UMBC),\nT. Sakamoto (AGU) (i.e. the Swift-BAT team):\n \nUsing the data set from T-239 to T+843 sec from the recent telemetry downlink,\nwe report further analysis of BAT GRB 250327A (trigger #1299088)\n(Parsotan, et al., GCN Circ. 39877).  The BAT ground-calculated position is\nRA, Dec = 248.209, 61.610 deg which is \n   RA(J2000)  =  16h 32m 50.1s \n   Dec(J2000) = +61d 36' 35.4\" \nwith an uncertainty of 2.2 arcmin, (radius, sys+stat, 90% containment).\nThe partial coding was 10%.\n \nThe mask-weighted light curve shows a single main pulse lasting ~60 sec composed\nof several shorter pulses. The remainder of the burst emission is included in a \ndim tail. The T90 (15-350 keV) is 91.008 +- 12.21 sec (estimated error including \nsystematics).\n \nThe time-averaged spectrum from T+1.67 to T+109.928 sec is best fit by a simple\npower-law model.  The power law index of the time-averaged spectrum is\n1.28 +- 0.12.  The fluence in the 15-150 keV band is 7.6 +- 0.5 x 10^-06 erg/cm2.\nThe 1-sec peak photon flux measured from T+24.49 sec in the 15-150 keV band\nis 2.1 +- 0.7 ph/cm2/sec.  All the quoted errors are at the 90% confidence\nlevel. \n \nThe results of the batgrbproduct analysis are available at\nhttps://swift.gsfc.nasa.gov/results/batgrbcat/BAT_refined_circular/1299088"
}