{
  "subject": "GRB 240411B: Swift-BAT refined analysis",
  "submittedHow": "web",
  "createdOn": 1712943346156,
  "circularId": 36072,
  "submitter": "Mike Moss at NASA GSFC <mikejmoss3@gmail.com>",
  "eventId": "GRB 240411B",
  "body": "A. Y. Lien (U Tampa), S. D. Barthelmy (GSFC), \nH. A. Krimm (NSF), S. Laha (GSFC/UMBC),\nC. B. Markwardt (GSFC), M. J. Moss (GSFC),\nD. M. Palmer (LANL), T. Parsotan (GSFC),\nT. Sakamoto (AGU) (i.e. the Swift-BAT team):\n \nUsing the data set from T-239 to T+963 sec from the recent telemetry downlink,\nwe report further analysis of BAT GRB 240411B (trigger #1221183)\n(Parsotan, et al., GCN Circ. 36063).  The BAT ground-calculated position is\nRA, Dec = 231.562, -2.172 deg which is \n   RA(J2000)  =  15h 26m 14.8s \n   Dec(J2000) = -02d 10' 20.9\" \nwith an uncertainty of 3.3 arcmin, (radius, sys+stat, 90% containment).\nThe partial coding was 53%.\n \nThe mask-weighted light curve shows two spikes separated by an interval of ~15 seconds. \nThe estimated T90 (15-350 keV) is 33.26 +- 1.49 sec (estimated error including systematics).\n \nThe time-averaged spectrum from T-0.37 to T+33.92 sec is best fit by a simple\npower-law model.  The power law index of the time-averaged spectrum is\n1.69 +- 0.41.  The fluence in the 15-150 keV band is 4.9 +- 1.2 x 10^-07 erg/cm2.\nThe 1-sec peak photon flux measured from T+32.87 sec in the 15-150 keV band\nis 0.9 +- 0.3 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/1221183",
  "bibcode": "2024GCN.36072....1L"
}