GCN Circular 33011
GRB 221201A: Fermi GBM observation C. Malacaria (ISSI) and C. Meegan (UAH) report on behalf of the Fermi GBM Team: "At 12:24:45.31 UT on 01 December 2022, the Fermi Gamma-Ray Burst Monitor (GBM) triggered and located GRB 221201A (trigger 691590290 / 221201517). This event was also observed by Swift/BAT and�� Swift/XRT (GCN 32998). The GBM position is reported in the Fermi-GBM Final on-ground Localization (GCN 32997) and is consistent with the Swift position. The angle from the Fermi LAT boresight is 125 degrees. The GBM light curve shows a single pulse with a duration (T90) of about 29 s (50-300 keV). The time-averaged spectrum from T0-0 s to T0+15 s is best fit by a Band function with Epeak = 144 +/- 7 keV, alpha = -0.57 +/- 0.07, and beta = -2.5 +/- 0.1 The event fluence (10-1000 keV) in this time interval is (1.59 +/- 0.03)E-05 erg/cm^2. The 1-sec peak photon flux measured starting from T0+6.8 s in the 10-1000 keV band is 20.5 +/- 0.6 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/"