TITLE: GCN CIRCULAR NUMBER: 22295 SUBJECT: GRB 180102A: Fermi GBM detection DATE: 18/01/02 20:38:51 GMT FROM: Peter Veres at UAH P. Veres (UAH) reports on behalf of the Fermi GBM Team: "At 15:49:47.21 UT on 2 January 2018, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 180102A (trigger 536600992 / 180102660) which was also detected by Swift/BAT (Page et al., GCN 22292). The GBM on-ground location is consistent with the Swift position. The angle from the Fermi LAT boresight at the GBM trigger time is 60 degrees. The GBM light curve consists of a single pulse with a duration (T90) of about 16 s (50-300 keV). The time-averaged spectrum from T0-6.1 s to T0+2.0 s is best fit by a power law function with an exponential high-energy cutoff. The power law index is -0.40 +/- 0.44 and the cutoff energy, parameterized as Epeak, is 54.9 +/- 6.7 keV. The event fluence (10-1000 keV) in this time interval is (4.31 +/- 0.45)E-7 erg/cm^2. The 1-sec peak photon flux measured starting from T0+0.7 s in the 10-1000 keV band is 1.76 +/- 0.19 ph/s/cm^2. A Band function fits the spectrum equally well with Epeak= 41.8 +/- 9.2 keV, alpha = 0.59 +/- 1.18 and beta = 2.52 +/- 0.35. The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog."