GCN Circular 23658
A. von Kienlin (MPE) reports on behalf of the Fermi GBM Team: "At 05:12:49.45 UT on 09 January 2019, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 190109A (trigger 568703574 / 190109217), which was also detected by the Swift/BAT (Gropp et al. 2019, GCN 23642) The GBM on-ground location is consistent with the Swift position. The angle from the Fermi LAT boresight at the GBM trigger time is 65 degrees. The GBM light curve shows a structured emission with a duration (T90) of about 120 s (50-300 keV). The time-averaged spectrum from T0-4.096 s to T0+114.690 s is best fit by a Band function with Epeak = 46.8 +/- 2.2 keV, alpha = 1.3 +/- 0.3, and beta = -2.71 +/- 0.13 The event fluence (10-1000 keV) in this time interval is (7.6 +/- 0.4)E-06 erg/cm^2. The 1.024-sec peak photon flux measured starting from T0+30.91 s in the 10-1000 keV band is 2.6 +/- 0.2 ph/s/cm^2. The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog."