GCN Circular 29387
C. Fletcher (USRA), B. Hristov (UAH) and C. Meegan (UAH) report on behalf of the Fermi GBM Team: At 20:10:31.30 UT on 02 February 2021, the Fermi Gamma-Ray Burst Monitor (GBM) triggered and located GRB 210202A (trigger 633989436 / 210202841). There was also a Fermi/LAT ground detection (R. Hamburg et al., GCN 29386). The Fermi GBM Final Real-time Localization was reported in GCN 29380. It is consistent with the Fermi/LAT human-generated position. The angle from the Fermi LAT boresight at the GBM trigger time is 45 degrees. The GBM light curve consists of multiple peaks with a duration (T90) of about 18 s (50-300 keV). The time-averaged spectrum from T0+0.003 s to T0+18.7 s is best fit by a power law function with an exponential high-energy cutoff. The power law index is -0.71 +/- 0.03 and the cutoff energy, parameterized as Epeak, is 297 +/- 12 keV. The spectrum is also well fit by a Band function with Epeak = 265 +/- 16 keV, alpha = -0.66 +/- 0.04, and beta = -2.5 +/- 0.2. The event fluence (10-1000 keV) in this time interval is (1.670 +/- 0.036)E-05 erg/cm^2. The 1-sec peak photon flux measured starting from T0+1.5 s in the 10-1000 keV band is 16 +/- 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/"