{
  "bibcode": "2009GCN..9418....1V",
  "body": "A.J. van der Horst (NASA/MSFC/ORAU) reports on behalf of the\nFermi GBM Team:\n\n\"At 20:28:40.05 UT on 16 May 2009, the Fermi Gamma-ray Burst Monitor\n(GBM) triggered and located GRB 090516C (trigger 264198522 / 090516.853).\nThe on-ground calculated location, using the Fermi GBM trigger data,\nis RA = 15.7, Dec = -13.7 (J2000 degrees, equivalent to\nJ2000 1h03m, -13d41'), with a statistical uncertainty of 3.5 degrees\n(radius, 1-sigma containment, statistical only; there is additionally\na systematic error which is currently estimated to be 2 to 3 degrees).\nThe angle from the Fermi LAT boresight is 69 degrees.\n\nThe GBM light curve consists of one short spike and some smaller peaks,\nwith a total duration (T90) of 15 s (8-1000 keV). The time-averaged\nspectrum from T0+0.00 to T0+15.26 s is adequately fit by a power law\nwith an exponential high-energy cutoff. The index is -1.51 +/- 0.08\nand the cutoff energy, parameterized as Epeak, is 210 +/- 68 keV\n(chi squared 372 for 360 d.o.f.). The Band function provides a\nsignificantly better fit (chi squared 365 for 359 d.o.f.) with a lower\nEpeak value, but the low-energy index alpha and the amplitude are\npoorly constrained: alpha is -0.44 +/- 0.81, beta is -1.81 +/- 0.06,\nand Epeak is 38 +/- 14.\nThe fluence (8-1000 keV) in this interval is (4.0 +/- 0.3)E-6 erg/cm^2.\nThe 1-sec peak photon flux measured starting from T0+0.0s in the\n8-1000 keV band is 7.7 +/- 0.4 ph/s/cm^2.\n\nThe spectral and temporal analysis results presented above are preliminary;\nfinal results will be published in the GBM GRB Catalog.\"",
  "circularId": 9418,
  "createdOn": 1242948741000,
  "email": "Alexander.J.VanDerHorst@nasa.gov",
  "subject": "GRB 090516C: Fermi GBM detection",
  "submitter": "Alexander van der Horst at NASA/MSFC  <Alexander.J.VanDerHorst@nasa.gov>",
  "eventId": "GRB 090516C"
}