TITLE: GCN CIRCULAR NUMBER: 15687 SUBJECT: GRB 140104B: Fermi GBM observation DATE: 14/01/05 18:42:56 GMT FROM: Shaolin Xiong at UAH Shaolin Xiong (UAH) reports on behalf of the Fermi GBM Team: "At 17:32:03.15 UT on 04 January 2014, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 140104B (trigger 410549526 / 140104731), which was also detected by the ground analysis of Fermi/LAT (Vianello et al. 2014, GCN 15684) The GBM on-ground location is consistent with the LAT position. The GBM light curve consists of multiple pulses with a duration (T90) of about 190 s (50-300 keV). The time-averaged spectrum from T0 to T0+200 s is well fit by a power law function with an exponential high-energy cutoff. The power law index is -1.23 +/- 0.06 and the cutoff energy, parameterized as Epeak, is 280 +/- 40 keV. The event fluence (10-1000 keV) in this time interval is (3.2 +/- 0.2)E-5 erg/cm^2. The 1-sec peak photon flux measured starting from T0+190.7 s in the 10-1000 keV band is 5.7 +/- 0.2 ph/s/cm^2. The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog."