{
  "bibcode": "2009GCN..8821....1C",
  "body": "Valerie Connaughton (UAH) reports on behalf of the Fermi GBM Team:\n\n\"At 15:22:01.05 UT on 17 Jan 2009, the Fermi Gamma-Ray Burst Monitor\ntriggered and located GRB 090117 (trigger 253898523 / 090117640)\nwhich was also detected by SuperAGILE (Donnarumma et al. 2009,\nGCN 8817).\n\nThe GBM on-ground location is consistent with the reported\nposition from SuperAGILE. The angle from the Fermi LAT boresight is\n51 degrees.\n\nThe GBM light curve shows a soft event with a single peak lasting\nabout 2 seconds superimposed on a lower-level continuum.\nThe burst duration (T90) is about 21 s (8-1000 keV).\nThe time-averaged spectrum from T0-5 s to T0+4 s is\nbest fit by a Band function with Epeak = 25 +/- 2 keV,\nalpha = -0.4 +/- 0.5, and beta = -2.5 +/- 0.1\n\nThe event fluence (8-1000 keV) in this time interval is\n(1.8 +/- 1.3)E-6 erg/cm^2, with a 1 sec peak flux starting\nat T0 of 9.6 +/- 4.2 ph/cm^2/s and a 0.256 sec peak flux starting\nat T0+0.256 sec of 18.6 +/- 8.0 ph/cm^2/s.\n\nIn view of the soft spectrum and the position of the burster close to\nthe Galactic plane, other spectral forms were investigated that are\nmore typical of galactic transient sources.   Of these, the best fit was\nobtained using a thermal Bremmstrahlung model with kT = 49. \nThe Band GRB function was preferred statistically with delta chi2\n= -5 for 1 extra parameter. It is likely, therefore, that this is a soft\nGRB rather than a new galactic transient.\n\nThe spectral analysis results presented above are preliminary;\nfinal results will be published in the GBM GRB Catalog.\"",
  "circularId": 8821,
  "createdOn": 1232258306000,
  "email": "valerie@nasa.gov",
  "subject": "GRB 090117 - Fermi GBM Observations",
  "submitter": "Valerie Connaughton at MSFC  <valerie@nasa.gov>",
  "eventId": "GRB 090117"
}