TITLE: GCN CIRCULAR NUMBER: 19061 SUBJECT: GRB 160223B: Fermi GBM observation DATE: 16/02/23 15:27:58 GMT FROM: Andreas von Kienlin at MPE A. von Kienlin, H.-F. Yu, and K. Toelge (all MPE) report on behalf of the Fermi GBM Team: "At 09:59:01.51 UT on 23 February 2016, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 160223B (trigger 477914345 / 160223416), which was also detected by INTEGRAL (Götz et al. 2016, GCN 19059) The GBM on-ground location is consistent with the INTEGRAL position. The angle from the Fermi LAT boresight at the GBM trigger time is 49 degrees. The GBM light curve shows a structured pulse with a duration (T90) of about 17 s (50-300 keV). The time-averaged spectrum from T0-2.560 s to T0+16.896 s is best fit by a power law function with an exponential high-energy cutoff. The power law index is -0.90 (+0.08/-0.07) and the cutoff energy, parameterized as Epeak, is 560 (+110 /-80) keV The event fluence (10-1000 keV) in this time interval is (5.9 +/- 0.3)E-06 erg/cm^2. The 1.024-sec peak photon flux measured starting from T0+0.256 s in the 10-1000 keV band is 3.1 +/- 0.2 ph/s/cm^2. The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog."