TITLE: GCN CIRCULAR NUMBER: 27239 SUBJECT: GRB 200227A: Fermi GBM observation DATE: 20/02/27 14:19:53 GMT FROM: Elisabetta Bissaldi at INFN,Bari E. Bissaldi (Politecnico and INFN Bari) reports on behalf of the Fermi GBM Team: "At 07:20:08.70 UT on 27 February 2020, the Fermi Gamma-Ray Burst Monitor (GBM) triggered and located GRB 200227A (trigger 604480813 / 200227306), which was also detected by the Swift/BAT (Laha et al. 2020, GCN 27234). The GBM on-ground location is consistent with the Swift position. The angle from the Fermi LAT boresight at the GBM trigger time is 19 degrees. The GBM light curve shows a single broad peak with a duration (T90) of about 24 s (50-300 keV). The time-averaged spectrum from T0 to T0+24 s is adequately fit by a Band function with Epeak = 139 +/- 10 keV, alpha = -0.95 +/- 0.05, and beta = -2.28 +/- 0.11. The event fluence (10-1000 keV) in this time interval is (1.41 +/- 0.04)E-05 erg/cm^2. The 1-sec peak photon flux measured starting from T0+7.1 s in the 10-1000 keV band is 8.8 +/- 0.4 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/"