{
  "bibcode": "2008GCN..8206....1C",
  "body": "Valerie Connaughton (UAH) and Alexander van der Horst (NASA/MSFC), \nreport on behalf of the Fermi Gamma-ray Burst Monitor Team:\n\n\"At 21:16:10 UT on 04 September 2008, the Fermi Gammay-Ray Burst Monitor\n(GBM) triggered and located a soft GRB 080904 (trigger 242255765 /\n080904.886). The on-ground calculated location, using the GBM trigger\ndata, is RA = 215.1, Dec = -32.3 (J2000 degrees) (equivalent to J2000\n14h 20m, -32d 18m), with an uncertainty of 1.4 degrees (radius, 1-sigma\ncontainment, statistical only; there is additionally a systematic error\nwhich is currently estimated to be 2 to 3 degrees).  The angle from the\nLarge Area Telescope (LAT) boresight is 23 degrees.\n\nThis GRB was about 22 s long with 1 peak, showing some substructure on\nthe pulse rise.   The time-averaged spectrum from T-4 to T+17 s is best\nfit by a Band function with the following parameters:\nalpha= 0.0 +/- 0.17\nbeta = -2.70 +/- 0.08\nEpeak = 35 +/- 1 keV\n\nThe fluence between 50 and 300 keV over these 21 seconds is 2.25 +/-\n0.49 x 10^-6 erg/cm^2 with a peak flux of 3.5 +/- 0.7 photons/cm^2/sec.\nBetween 15 and 150 keV the peak flux is 12.7 +/- 2.7 photons/cm^2/sec.\n\nAccording to the prescription of Sakamoto et al. 2008 (ApJ, 679, 570),\nthe ratio of the fluences in the 25-50 keV and 50-100 keV energy\nranges of 1.37 +/- 0.36 puts this in the X-Ray Flash category (XRF)\nbut the error bar allows it to be considered, alternatively,\nan X-Ray Rich event (XRR).\n\nThe spectral analysis results presented above are preliminary; the\nfinal results will be published in the GBM GRB Catalog.\"",
  "circularId": 8206,
  "createdOn": 1221011563000,
  "email": "valerie@nasa.gov",
  "subject": "GRB 080904:  Fermi Gamma-ray Burst Monitor detection",
  "submitter": "Valerie Connaughton at MSFC  <valerie@nasa.gov>",
  "eventId": "GRB 080904"
}