GCN Circular 19264
A. von Kienlin (MPE/UAH) and C. Meegan (UAH) report on behalf of the Fermi GBM Team: "At 12:04:36.80 UT on 6 April 2016, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 160406A (trigger 481637080 / 160406503), which was also detected by IPN (Kozlova et al. 2016, GCN 19259). The GBM on-ground location is consistent with the IPN triangulated position. The angle from the Fermi LAT boresight at the GBM trigger time is 77.5 degrees. The GBM light curve shows a single pulse with a duration (T90) of about 0.4 s (50-300 keV). The time-averaged spectrum from T0-0.064 s to T0+0.192 s is best fit by a power law function with an exponential high-energy cutoff. The power law index is -0.75 (+0.13/-0.12) and the cutoff energy, parameterized as Epeak, is 700 (+210 /-130) keV. The event fluence (10-1000 keV) in this time interval is (7.2 +/- 0.4)E-07 erg/cm^2. The 0.064-sec peak photon flux measured starting from T0+0.0 s in the 10-1000 keV band is 17 +/- 1 ph/s/cm^2. The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog."