TITLE: GCN CIRCULAR NUMBER: 21019 SUBJECT: GRB 170419B: Fermi GBM observation DATE: 17/04/20 09:08:01 GMT FROM: Andreas von Kienlin at MPE P. Veres and C. Meegan (both UAH) report on behalf of the Fermi GBM Team: "At 21:33:46.807 UT on 19 April 2016, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 170419B (trigger 514330431 / 170419898). which was also detected by the Swift/BAT (Cholden-Brown et al., GCN 21016). The GBM on-ground location is consistent with the Swift position. The angle from the Fermi LAT boresight at the GBM trigger time is 41 degrees. The GBM light curve shows a single pulse with a duration (T90) of about 24 s (50-300 keV). The time-averaged spectrum from T0-0.5 s to T0+5.1 s is best fit by a Band function with Epeak = 116 +/- 19 keV, alpha = -0.03 +/- 0.29, and beta = -2.07 +/- 0.15. The event fluence (10-1000 keV) in this time interval is (2.4 +/- 0.2)E-6 erg/cm^2. The 1-sec peak photon flux measured starting from T0+1.2 s in the 10-1000 keV band is 3.8 +/- 0.2 ph/s/cm^2. The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog."