{
  "bibcode": "2015GCN.17388....1P",
  "body": "V. Pelassa (UAH) reports on behalf of the Fermi GBM Team:\n\n\"At 23:59:08.27 UT on 02 Feb 2015, the Fermi Gamma-Ray Burst Monitor\ntriggered and located GRB 150202B (trigger 444614351 / 150202999).\n\nThe on-ground calculated location, using the GBM trigger data, is\nRA = 86.8, Dec = 58.6 (J2000 degrees, equivalent to +05h 47m, +58d 32'),\nwith an uncertainty of 1.0 degrees (radius, 1-sigma containment,\nstatistical only; there is additionally a systematic error which is\ncurrently estimated to be 2 to 3 degrees). The angle from the Fermi LAT\nboresight is 17 degrees.  This trigger resulted in an Autonomous Repoint\nRequest (ARR) that was not accepted by the spacecraft.  Following\nthis observation the Fermi Large Area Telescope also detected\nthis burst in the ground-based analysis (Axelsson et al. 2015, GCN 17385).\n\nThis GRB was also detected by Integral/SPI-ACS.\n\nThe GBM light curve consists of a bright peak lasting about 25 s, \nfollowed at T0+ 100 s by a fainter second episode of emission, \nwith a total duration (T90) of about 167 s (50-300 keV). \nThe 1.024-sec peak photon flux measured starting from T0+7.808 s \nin the 10-1000 keV band is 23.8 +/- 0.4 ph/s/cm^2.\n\nThe time-averaged spectrum of the first episode, from T0-5.120 s to\nT0+24.576 s, is best fit by a Band function with Epeak = 253 +/- 12 keV,\nalpha = -0.82 +/- 0.02, and beta = -2.36 +/- 0.13. The event fluence \n(10-1000 keV) in this time interval is (3.15 +/- 0.05)E-05 erg/cm^2.\n\nThe time-averaged spectrum of the second episode, from T0+103.426 s to\nT0+205.827 s, is well fit a power law function with an exponential\nhigh-energy cutoff. The power law index is -1.23 +/- 0.13 and\nthe cutoff energy, parameterized as Epeak, is 154 +/- 36 keV. \nThe event fluence (10-1000 keV) in this time interval \nis (1.37 +/- 0.15)E-06 erg/cm^2.\n\nThe spectral analysis results presented above are preliminary;\nfinal results will be published in the GBM GRB Catalog.\"\n\n[GCN OPS NOTE(03feb15): The third sentence in the second paragraph\nwas changed to say the ARR was rejected by the spacecraft.]",
  "circularId": 17388,
  "createdOn": 1422961737000,
  "email": "sptfung@mpe.mpg.de",
  "subject": "GRB 150202B: Fermi GBM detection",
  "submitter": "Hoi-Fung Yu at MPE  <sptfung@mpe.mpg.de>",
  "eventId": "GRB 150202B"
}