TITLE: GCN CIRCULAR NUMBER: 16680 SUBJECT: GRB 140810A: Fermi GBM observation DATE: 14/08/11 10:58:02 GMT FROM: Oliver Roberts at UCD/Fermi Oliver Roberts (UCD) and Matthew Stanbro (UAH) report on behalf of the Fermi GBM Team: "At 18:46:10.09 UT on the 10th of August 2014, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 140810A (trigger 429389173 / 140810782), which was also detected by the LAT (Bissaldi et al. 2014, GCN 16678). The trigger resulted in an Autonomous Repoint Request (ARR) that was accepted. The GBM on-ground location is consistent with the LAT position. The angle from the Fermi LAT boresight is 122 degrees. The GBM light curve consists of multiple peaks with a duration (T90) of about 82 s (50-300 keV). The time-averaged spectrum from T0-3.58 s to T0+107.01 s is well fit by a power law function with an exponential high-energy cutoff. The power law index is -1.01 +/- 0.01 and the cutoff energy, parameterised as Epeak, is 302 +/- 7 keV. The event fluence (10-1000 keV) in this time interval is (110.42 +/- 0.07)E-06 erg/cm^2. The 1.024-sec peak photon flux measured from T0+6.6 s in the 10-1000 keV band, is 35.98+/-0.65 ph/s/cm^2. The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog."