{
  "bibcode": "2017GCN.21030....1S",
  "body": "M. Stanbro and C. Meegan (UAH) report on behalf of the Fermi GBM Team:\n\n\"At 17:15:08.35 UT on 23 April 2017, the Fermi Gamma-Ray Burst Monitor\ntriggered and located GRB 170423A (trigger 514660513 / 170423719).\nThe on-ground calculated location, using the GBM trigger\ndata, is RA = 344.34, DEC = -4.26, with an uncertainty\nof 1.17 degrees (radius, 1-sigma containment,\nstatistical only; there is additionally a systematic\nerror which we have characterized as a core-plus-tail model, with 90% of\nGRBs having a 3.7 deg error and a small tail suffering a larger than 10 deg\nsystematic error. [Connaughton et al. 2015, ApJS, 216, 32] ).\n\nThe trigger resulted in an Autonomous Repoint Request (ARR)\nby the GBM Flight Software owing to the high peak flux\nof the GRB. This ARR was accepted and the spacecraft slewed to the GBM\nin-flight\nlocation. The initial angle from the Fermi LAT boresight to\nthe GBM ground location is 54 degrees.\n\nThe GBM light curve consists of several peaks\nwith a duration (T90) of about 47 s (50-300 keV).\nThe time-averaged spectrum from T0+2.05 s to T0+49.15 s is\nbest fit by a Band function with Epeak = 97 +/- 5 keV,\nalpha = -1.04 +/- 0.04, and beta = -2.15 +/- 0.04.\n\nThe event fluence (10-1000 keV) in this time interval is\n(2.6 +/- 0.04)E-05 erg/cm^2. The 1-sec peak photon flux measured\nstarting from T0+10.8 s in the 10-1000 keV band\nis 18.4 +/- 0.4 ph/s/cm^2.\n\nThe spectral analysis results presented above are preliminary;\nfinal results will be published in the GBM GRB Catalog.\"",
  "circularId": 21030,
  "createdOn": 1492992269000,
  "email": "mcs0001@uah.edu",
  "subject": "GRB 170423A: Fermi GBM detection",
  "submitter": "Matthew Stanbro at UAH/Fermi  <mcs0001@uah.edu>",
  "eventId": "GRB 170423A"
}