TITLE: GCN CIRCULAR NUMBER: 16754 SUBJECT: GRB 140828A: Fermi GBM observation DATE: 14/08/29 07:52:08 GMT FROM: Andreas von Kienlin at MPE A. von Kienlin (MPE) reports on behalf of the Fermi GBM Team: "At 06:54:12.18 UT on 28 August 2014, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 140828A (trigger 430901655 / 140828288), which was also detected by the Swift/BAT (Melandri et al. 2014, GCN 16751) The GBM on-ground location is consistent with the Swift position. The angle from the Fermi LAT boresight is 57 degrees. The GBM light curve consists of a single pulse with a duration (T90) of about 24 s (50-300 keV). The time-averaged spectrum from T0-6.1 s to T0+16.4 s is best fit by a power law function with an exponential high-energy cutoff. The power law index is -1.5 +/- 0.1 and the cutoff energy, parameterized as Epeak, is 140 +/- 30 keV. The event fluence (10-1000 keV) in this time interval is (3.5 +/- 0.2)E-06 erg/cm^2. The 1.024-sec peak photon flux measured starting from T0+2.43 s in the 10-1000 keV band is 3.5 +/- 0.2 ph/s/cm^2. The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog."