TITLE: GCN CIRCULAR NUMBER: 13754 SUBJECT: GRB 120911A: Fermi GBM observation DATE: 12/09/12 07:02:43 GMT FROM: David Gruber at MPE David Gruber (MPE) reports on behalf of the Fermi GBM Team: "At 07:08:33.99 UT on 11 September 2012, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 120911A (trigger 369040116 / 120911298). which was also detected by the Swift/BAT (Cannizzo et al. 2012, GCN 13744). The GBM on-ground location is consistent with the Swift position. The angle from the Fermi LAT boresight is 11 degrees. The GBM light curve consists of two pulses with a duration (T90) of about 22 s (50-300 keV). The time-averaged spectrum from T0-4.6 s to T0+22.0 s is best fit by a power law function with an exponential high-energy cutoff. The power law index is -0.36 +/- 0.26 and the cutoff energy, parameterized as Epeak, is 64.2 +/- 5.1 keV The event fluence (10-1000 keV) in this time interval is (2.34 +/- 0.04)E-06 erg/cm^2. The 1-sec peak photon flux measured starting from T0-0.38 s in the 10-1000 keV band is 4.31 +/- 0.27 ph/s/cm^2. The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog."