GCN Circular 13642
Peter Jenke (MSFC/NPP) reports on behalf of the Fermi GBM Team: "At 15:34:55.09 UT on 11 August 2012, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 120811C (trigger 366392098 / 120811649) which was also detected by the Swift/BAT (Barthelmy et al. 2012, GCN 13622). The GBM on-ground location is consistent with the Swift position. The angle from the Fermi LAT boresight is 133 degrees. The GBM light curve consists of a single pulse with a duration (T90) of about 14.3 s (50-300 keV). The time-averaged spectrum from T0-6.14 s to T0+10.24 s is best fit by a power law function with an exponential high-energy cutoff. The power law index is -0.71 +/- 0.20 and the cutoff energy, parameterized as Epeak, is 54 +/- 3 keV. The event fluence (10-1000 keV) in this time interval is (2.98 +/- 0.08)E-06 ergs/cm^2. The 1-sec peak photon flux measured starting from T0+3.072 s in the 10-1000 keV band is 5.9304 +/- 0.55 ph/s/cm^2. The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog."