{
  "bibcode": "2015GCN.18726....1V",
  "body": "P Veres (UAH) and Kilian Toelge (MPE)\nreport on behalf of the Fermi GBM Team:\n\n\n\"At 01:44:07.69 UT on 27 December 2015, the Fermi Gamma-Ray Burst Monitor\ntriggered and located GRB 151227A (trigger 472873451 / 151227072).\n\n\nThe on-ground calculated location, using the GBM trigger\ndata, is RA = 205.5, DEC = +65.9 (J2000 degrees,\nequivalent to 13h 42m, 65d 52'), with an uncertainty\nof 1.5 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\nThis burst was also independently detected by INTEGRAL SPI-ACS.\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 in-flight\nlocation. The initial angle from the Fermi LAT boresight to\nthe best location is 32 degrees.\n\nThe GBM light curve consists of a single pulse\nwith a duration (T90) of about 3.4 s (50-300 keV).\nThe time-averaged spectrum from T0 to T0 + 8.9 s is\nbest fit by a power law function with an exponential\nhigh-energy cutoff.  The power law index is -0.91 +/- 0.05 and\nthe cutoff energy, parameterized as Epeak, is 155 +/- 7 keV.\n\nThe event fluence (10-1000 keV) in this time interval is\n(5.0 +/- 0.1)E-6 erg/cm^2. The 1-sec peak photon flux measured\nstarting from T0+0.8 s in the 10-1000 keV band\nis 20.5 +/- 0.4 ph/s/cm^2.\n\n\nThe spectral analysis results presented above are preliminary;\nfinal results will be published in the GBM GRB Catalog.\"",
  "circularId": 18726,
  "createdOn": 1451213613000,
  "email": "Elisabetta.Bissaldi@uibk.ac.at",
  "subject": "GRB 151227A: Fermi GBM detection",
  "submitter": "Elisabetta Bissaldi at U.Innsbruk/IAPP  <Elisabetta.Bissaldi@uibk.ac.at>",
  "eventId": "GRB 151227A"
}