{
  "bibcode": "2009GCN..9698....1B",
  "body": "J. M. Burgess (UAH), A. Goldstein (UAH) and A. J. van der Horst\n(NASA/MSFC/ORAU) report on behalf of the Fermi GBM Team:\n\n\"At 17:02:56.91 UT on 20 July 2009, the Fermi Gamma-Ray Burst Monitor\ntriggered and located GRB 090720B (trigger 269802178 / 090720710).\nThe on-ground calculated location, using the GBM trigger\ndata, is RA = 203.0, DEC = -54.8 (J2000 degrees,\nequivalent to 13h 32m, -54d 48'), with an uncertainty\nof 2.9 degrees (radius, 1-sigma containment,\nstatistical only; there is additionally a systematic\nerror which is currently estimated to be 2 to 3 degrees).\nThe angle from the Fermi LAT boresight is 56 degrees.\n\nThis burst was also independently detected by INTEGRAL SPI-ACS.\n\nThe GBM light curve consists of two bright peaks with a\nduration (T90) of about 20 s (8-1000 keV).\nThe time-averaged spectrum from T0+0.0 s to T0+20.1 s is well\nfit by a power law function with an exponential high energy cutoff.\nThe power law index is -1.01 +/- 0.05 and the cutoff energy,  \nparameterized\nas Epeak, is 982 +/- 186 keV (chi squared 484 for 483 d.o.f.).\n\nThe event fluence (8-1000 keV) in this time interval is\n(1.06 +/- 0.03)E-5 erg/cm^2. The 1-sec peak photon flux measured\nstarting from T0+5.8 s in the 8-1000 keV band\nis 10.9 +/- 0.4 ph/s/cm^2.\n\nA Band function fits the spectrum equally well (chi squared 482 for\n482 d.o.f.) with Epeak= 924 +/- 201 keV, alpha = -1.00 +/- 0.05\nand beta = -2.43 +/- 0.47.\n\nThe temporal and spectral analysis results presented above are  \npreliminary;\nfinal results will be published in the GBM GRB Catalog.\"",
  "circularId": 9698,
  "createdOn": 1248271060000,
  "email": "james.burgess@uah.edu",
  "subject": "GRB 090720B: Fermi GBM detection",
  "submitter": "Michael Burgess at UAH  <james.burgess@uah.edu>",
  "eventId": "GRB 090720B"
}