GCN Circular 31392
Boyan A. Hristov (MPE/UAH) reports on behalf of the Fermi GBM Team: "At 04:01:02.60 UT on 04 January 2022, the Fermi Gamma-Ray Burst Monitor (GBM) triggered and located GRB 220104A (trigger 662961667 / 220104167) which was also detected by GECAM (Z. W. Guo et al. 2022, GCN 31382). The GBM on-ground location (GCN 31380) is consistent with the GECAM position. The GBM light curve consists of multiple peaks with a duration (T90) of about 2.624 s (50-300 keV). The time-averaged spectrum from T0-0.128 s to T0+0.320 s is best fit by a simple power law function with index -1.28 +/- 0.05. The event fluence (10-1000 keV) in this time interval is (3.5 +/- 0.34)E-07 erg/cm^2. The 64-miliseconds peak photon flux measured starting from T0-0.064 s in the 10-1000 keV band is 4.00 +/- 0.98 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/"