GCN Circular 24562
O.J. Roberts (USRA/NASA-MSFC) reports on behalf of the Fermi GBM Team: "At 04:33:03.14 UT on the 15th May 2019, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 190515A (trigger 579587588 / 190515190), which was also detected by the LAT (Kocevski et al. 2019, GCN 24560) The GBM on-ground location is consistent with the LAT position. The angle from the Fermi LAT boresight is 44 degrees. The GBM light curve shows a bright short spike with a duration (T90) of about 0.5 s (10-1000 keV). The time-averaged spectrum from T0-0.26 s to T0+0.38 s is best fit by a power law function with an exponential high-energy cutoff. The power law index is -0.4 +/- 0.2 and the cutoff energy, parameterized as Epeak, is 960 +/- 251 keV. The event fluence (10-1000 keV) in this time interval is (1.233 +/- 0.070)E-06 erg/cm^2. The 64-msec peak photon flux measured starting from T0+0.2 s in the 10-1000 keV band is 8.2 +/- 0.9 ph/s/cm^2." The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog: https://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html For Fermi GBM data and info, please visit the official Fermi GBM Support Page: https://fermi.gsfc.nasa.gov/ssc/data/access/gbm/"