{
  "bibcode": "2017GCN.20838....1S",
  "body": "M. Stamatikos (OSU), S. D. Barthelmy (GSFC),\nJ. R. Cummings (CPI), N. Gehrels (GSFC),\nH. A. Krimm (NSF/USRA), A. Y. Lien (GSFC/UMBC),\nC. B. Markwardt (GSFC), D. M. Palmer (LANL),\nT. Sakamoto (AGU), T. N. Ukwatta (LANL)\n(i.e. the Swift-BAT team):\n\nUsing the data set from T-12 to T+963 sec from the recent telemetry downlink,\nwe determine that BAT trigger #741528 (Lien et al., GCN Circ. 20832) is indeed\na GRB, which also detected by Fermi GBM (Hui et al., GCN Circ. 20835). We report\nfurther analysis of BAT GRB 170307A (trigger #741528).\nThe BAT ground-calculated position is\nRA, Dec = 13.510, 9.538 deg which is\n   RA(J2000)  =  00h 54m 02.5s\n   Dec(J2000) = +09d 32' 17.9\"\nwith an uncertainty of 2.5 arcmin, (radius, sys+stat, 90% containment).\nThe partial coding was 43%.\n\nThe mask-weighted light curve shows a weak structure with several overlapping\npulses that starts at ~T+55 s and ends at ~T+125 s. The burst emission might\nstart before it came into the BAT FOV at ~T-12 s. T90 (15-350 keV) is\n56.92 +- 27.40 sec (estimated error including systematics).\n\nThe time-averaged spectrum from T+55.33 to T+124.69 sec is best fit by a simple\npower-law model.  The power law index of the time-averaged spectrum is\n1.88 +- 0.23.  The fluence in the 15-150 keV band is 1.3 +- 0.2 x 10^-6 erg/cm2.\nThe 1-sec peak photon flux measured from T+69.72 sec in the 15-150 keV band\nis 1.4 +- 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\nhttp://gcn.gsfc.nasa.gov/notices_s/741528/BA/",
  "circularId": 20838,
  "createdOn": 1488981564000,
  "email": "amy.y.lien@nasa.gov",
  "subject": "GRB 170307A (trigger 741528): Swift-BAT refined analysis",
  "submitter": "Amy Lien at GSFC  <amy.y.lien@nasa.gov>",
  "eventId": "GRB 170307A"
}