TITLE: GCN CIRCULAR NUMBER: 28675 SUBJECT: GRB 201017A: Fermi GBM detection DATE: 20/10/18 00:40:30 GMT FROM: Suraj Poolakkil at UAH S. Poolakkil (UAH), C. Meegan (UAH) and A. von Kienlin (MPE) report on behalf of the Fermi GBM Team: "At 09:46:32.63 UT on 17 October 2020, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 201017A(trigger 624620797 / 201017407), which was also detected by the Swift/BAT (A. D'Ai et al. 2020, GCN 28666). The GBM on-ground location is consistent with the Swift position. The angle from the Fermi LAT boresight at the GBM trigger time is 98 degrees. The GBM light curve consists of a single peak followed by some extended emission with a duration (T90) of about 9 s (50-300 keV). The time-averaged spectrum from T0-4.09 s to T0+5.12 s is best fit by a power law function with an exponential high-energy cutoff. The power law index is -1.20 +/- 0.17 and the cutoff energy, parameterized as Epeak, is 144 +/- 35 keV. The event fluence (10-1000 keV) in this time interval is (1.402 +/- 0.166)E-06 erg/cm^2. The 1-sec peak photon flux measured starting from T0-0.89 s in the 10-1000 keV band is 2.9 +/- 0.3 ph/s/cm^2. The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog: https://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html For Fermi GBM data and info, please visit the official Fermi GBM Support Page: https://fermi.gsfc.nasa.gov/ssc/data/access/gbm/"