GCN Circular 28362
S. Lesage (UAH) and C. Meegan (UAH) report on behalf of the Fermi GBM Team: "At 00:44:19.25 UT on 3 September 2020, the Fermi Gamma-Ray Burst Monitor (GBM) triggered and located GRB 200903A (trigger 620786664 / 200903031) which was also detected by the Swift/BAT (A. P. Beardmore et al. 2020, GCN 28350). The Fermi GBM Final Real-time Localization (GCN 28349) is consistent with the Swift position. The angle from the Fermi LAT boresight at the GBM trigger time is ~61 degrees. The GBM light curve shows a single bright peak with a duration (T90) of about 26.9 s (50-300 keV). The time-averaged spectrum from T0-5.4 s to T0+21.5 s is best fit by a power law function with an exponential high-energy cutoff. The power law index is -0.9 +/- 0.1 and the cutoff energy, parameterized as Epeak, is 111.4 +/- 8.9 keV. The event fluence (10-1000 keV) in this time interval is (4.6 +/- 0.2)E-06 erg/cm^2. The 1.024-sec peak photon flux measured starting from T0+3.3 s in the 10-1000 keV band is 6.03 +/- 0.24 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/"