{
  "bibcode": "2009GCN..9184....1C",
  "body": "Valerie Connaughton (UAH) reports on behalf of the Fermi GBM Team:\n\n\"At 19:35:24.92 UT on 18 April 2009, the Fermi Gamma-Ray Burst Monitor\ntriggered and located GRB 090418C (trigger 261776126 / 090418816).\n\nThe on-ground calculated location, using the GBM trigger\ndata, is RA = 262.8, DEC = -28.3 (J2000 degrees,\nequivalent to 17 h 31 m, -28 d 18 '), with an uncertainty\nof 14.4 degrees (radius, 1-sigma containment,\nstatistical only; there is additionally a systematic\nerror which is currently estimated to be 2 to 3 degrees).\n \nThe angle from the Fermi LAT boresight is 58 degrees.\n\nThe GBM light curve shows a short, double-peaked burst\nwith a duration (T90) of about 0.6 s (8-1000 keV).\nThe time-averaged spectrum from T0-0.128 s to T0+0.256 s is\nwell fit by a power law with index -1.27 +/- 0.04, though\nformally it is best fit by a power law function with an exponential\nhigh energy cutoff.  The power law index in this case\nis -0.94 +/- 0.08 and the cutoff energy, parameterized as Epeak,\nlies above 1 MeV.\n\nThe event fluence (8-1000 keV) in this time interval is\n(6.0 +/- 0.3)E-7 erg/cm^2. The 0.128-sec peak photon flux measured\nstarting from T0-0.128 s in the 8-1000 keV band\nis 8.5 +/- 0.5 ph/s/cm^2.\n\nThe spectral analysis results presented above are preliminary;\nfinal results will be published in the GBM GRB Catalog.\"",
  "circularId": 9184,
  "createdOn": 1240362493000,
  "email": "valerie@nasa.gov",
  "subject": "GRB 090418C: Fermi GBM Detection",
  "submitter": "Valerie Connaughton at MSFC  <valerie@nasa.gov>",
  "eventId": "GRB 090418C"
}