GCN Circular 22585
C. Malacaria (NASA-MSFC/USRA) reports on behalf of the Fermi GBM Team: "At 09:44:59.37 UT on 02 April 2018, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 180402A (trigger 544355104 / 180402406). The event was also detected by the Swift/BAT (Lien et al. 2018, GCN 22580). The GBM on-ground location is consistent with the Swift position. The LAT boresight angle is 90 degrees. The duration (T90) is 0.448 +/- 0.326 s (8-1000 keV). The time-averaged spectrum from T0-0.1 s to T0+0.2 s is best fit by a Band function. The best-fit parameters are: Alpha = 2.23 +/- 2.03, Beta = -1.35 +/- 0.04, Epeak = 123.80 +/- 44.00 keV. The event fluence (8-1000 keV) in this time interval is (8.69 +/- 0.62)E-07 erg/cm^2. The 1-sec peak photon flux measured starting from T0+0 s in the 10-1000 keV band is 17.5 +/- 1.4 ph/s/cm^2. The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog."