GCN Circular 31816
P. Veres (UAH), E. Bissaldi (Politecnico and INFN Bari) and C. Meegan (UAH) report on behalf of the Fermi GBM Team: "At 10:17:40.89 UT on 1 April 2022, the Fermi Gamma-Ray Burst Monitor (GBM) triggered and located GRB 220401A (trigger 670501065 / 220401429). The localization was reported in GCN 31811. The GBM lightcurve consists of two emission episodes with a duration (T90) of about 39.2 s (50-300 keV). The time-averaged spectrum from T0-8.2 s to T0+38.9 s is best fit by a power law function with an exponential high-energy cutoff. The power law index is -1.37 +/- 0.08 and the cutoff energy, parameterized as Epeak, is 46 +/- 2 keV. The event fluence (10-1000 keV) in this time interval is (2.42 +/- 0.06)E-6 erg/cm^2. The 1-sec peak photon flux measured starting from T0+7.0 s in the 10-1000 keV band is 7.8 +/- 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/"