{
  "bibcode": "2018GCN.23203....1P",
  "body": "D. M. Palmer (LANL), S. D. Barthelmy (GSFC),\nJ. R. Cummings (CPI), A. D'Ai (INAF-IASFPA),\nH. A. Krimm (NSF/USRA), A. Y. Lien (GSFC/UMBC),\nC. B. Markwardt (GSFC), T. Sakamoto (AGU),\nM. Stamatikos (OSU), T. N. Ukwatta (LANL)\n(i.e. the Swift-BAT team):\n\nUsing the data set from T-240 to T+962 sec from the recent telemetry downlink,\nwe report further analysis of BAT GRB 180904A (trigger #859282)\n(D'Ai et al., GCN Circ. 23194).  The BAT ground-calculated position is\nRA, Dec = 274.260, 46.640 deg which is\n  RA(J2000)  =  18h 17m 02.4s\n  Dec(J2000) = +46d 38' 23.3\"\nwith an uncertainty of 2.4 arcmin, (radius, sys+stat, 90% containment).\nThe partial coding was 56%.\n\nThe mask-weighted light curve shows a weak structure that starts at ~T0\nand ends at ~T+6 s. T90 (15-350 keV) is 5.40 +- 0.89 sec (estimated error\nincluding systematics).\n\nThe time-averaged spectrum from T+0.28 to T+6.18 sec is best fit by a simple\npower-law model.  The power law index of the time-averaged spectrum is\n1.02 +- 0.30.  The fluence in the 15-150 keV band is 2.4 +- 0.4 x 10^-7 erg/cm2.\nThe 1-sec peak photon flux measured from T+5.14 sec in the 15-150 keV band\nis 0.5 +- 0.2 ph/cm2/sec.  All the quoted errors are at the 90% confidence\nlevel.\n\nThe results of the batgrbproduct analysis are available at\nhttp://gcn.gsfc.nasa.gov/notices_s/859282/BA/",
  "circularId": 23203,
  "createdOn": 1536161330000,
  "email": "amy.y.lien@nasa.gov",
  "subject": "GRB 180904A: Swift-BAT refined analysis",
  "submitter": "Amy Lien at GSFC  <amy.y.lien@nasa.gov>",
  "eventId": "GRB 180904A"
}