TITLE: GCN CIRCULAR NUMBER: 18798 SUBJECT: GRB 160101B: Fermi GBM detection DATE: 16/01/01 17:41:29 GMT FROM: Adam Goldstein at Fermi-GBM/UAH P Veres (UAH) and A. von Kienlin (MPE) report on behalf of the Fermi GBM Team: "At 05:10:12.86 UT on 01 January 2016, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 160101B (trigger 473317816 / 160101215). The on-ground calculated location, using the GBM trigger data, is RA = 1.4, DEC = 55.2 (J2000 degrees, equivalent to 0 h 5 m, 55 d 14 '), with an uncertainty of 1.4 degrees (radius, 1-sigma containment, statistical only; there is additionally a systematic error which we have characterized as a core-plus-tail model, with 90% of GRBs having a 3.7 deg error and a small tail suffering a larger than 10 deg systematic error. [Connaughton et al. 2015, ApJS, 216, 32] ). The angle from the Fermi LAT boresight at the GBM trigger time is 9 degrees. The GBM light curve consists of a single pulse with a duration (T90) of about 6.9 s (50-300 keV). The time-averaged spectrum from T0-0.5 s to T0+6.7 s is adequately fit by a power law function with an exponential high-energy cutoff. The power law index is -1.33 +/- 0.07 and the cutoff energy, parameterized as Epeak, is 952 +/- 468 keV. The event fluence (10-1000 keV) in this time interval is (2.73 +/- 0.14)E-6 erg/cm^2. The 1-sec peak photon flux measured starting from T0+0.3 s in the 10-1000 keV band is 2.1 +/- 0.2 ph/s/cm^2. The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog."