GCN Circular 31988
O.J. Roberts (USRA) and C. Meegan (UAH) report on behalf of the Fermi GBM Team: "At 19:51:50.74 UT on 01 May 2022, the Fermi Gamma-Ray Burst Monitor (GBM) triggered and located GRB 220501A (trigger 673127515 / 220501828), which was also detected by Swift/BAT (A. D'Ai et al. 2022, GCN 31982). The Fermi GBM Final Real-time Localization (GCN 31983) is consistent with the Swift position. The angle from the Fermi LAT boresight at the GBM trigger time is 94 degrees. The GBM light curve shows a FRED-like burst with a duration (T90) of about 51 s (50-300 keV). The time-averaged spectrum from T0-3.6 s to T0+47.6 s is best fit by a power law function with an exponential high-energy cutoff. The power law index is -0.49 +/- 0.18 and the cutoff energy, parameterized as Epeak, is 114 +/- 11 keV The event fluence (10-1000 keV) in this time interval is (3.53 +/- 0.24)E-06 erg/cm^2. The 1-sec peak photon flux measured starting from T0+2.0 s in the 10-1000 keV band is 2.5 +/- 0.2 ph/s/cm^2. The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog: 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/"