{
  "bibcode": "2009GCN.10266....1M",
  "body": "S. McBreen (UCD/MPE) reports on behalf of\nthe Fermi GBM Team:\n\n\"At 09:49:57.96 UT on 08 December 2009, the Fermi Gamma-Ray Burst Monitor\ntriggered and located GRB 091208B (trigger 281958599 / 091208410)\nwhich was also detected by the Swift-BAT (Pagani et al. 2009, GCN 10256).\nThe GBM on-ground location is consistent with the Swift position.\nThis burst was also independently detected by INTEGRAL SPI-ACS.\n\nThe angle from the Fermi LAT boresight is 56 degrees.\nMoreover, this burst was bright enough to result in\na Fermi spacecraft repointing maneuver.\n\nThe GBM light curve consists of two pulses\nwith a duration (T90) of about 15 s (8-1000 keV).\nThe time-averaged spectrum from T0-0.128 s to T0+14.592 s is\nwell fit by a power law function with an exponential\nhigh energy cutoff.  The power law index is -1.48 (+0.05/-0.05) and\nthe cutoff energy, parameterized as Epeak, is 144.20 (+18.00/-13.90) keV\n(CSTAT 829 for 604 d.o.f.).\n\nThe event fluence (8-1000 keV) in this time interval is\n(5.8 +/- 0.2)E-06 erg/cm^2. The 0.128 sec peak photon flux measured\nstarting from T0+8.45 s in the 8-1000 keV band is 32.4 +/- 1.1 ph/s/cm^2.\n\nA Band function fits the spectrum equally well (CSTAT 827 for 603 d.o.f.)\nwith Epeak= 124.00 (+20.10/-19.40) keV, alpha = -1.44 (+0.07/-0.06)\nand beta = -2.32 (+0.19/-0.47).\n\nThe spectral analysis results presented above are preliminary;\nfinal results will be published in the GBM GRB Catalog.\"",
  "circularId": 10266,
  "createdOn": 1260294167000,
  "email": "smcbreen@mpe.mpg.de",
  "subject": "GRB 091208B: Fermi GBM observation",
  "submitter": "Sheila McBreen at MPE  <smcbreen@mpe.mpg.de>",
  "eventId": "GRB 091208B"
}