TITLE: GCN CIRCULAR NUMBER: 16347 SUBJECT: GRB 140528A: Fermi GBM Detection DATE: 14/05/30 22:51:39 GMT FROM: Matthew Stanbro at UAH/Fermi Matthew Stanbro (UAH) reports on behalf of the Fermi GBM Team: "At 20:05:22.75 UT on 28 May 2014, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 140528A (trigger 423000325 / 140528837) which was triangulated by IPN (Golenetskii et al. 2014, GCN 16339). The GBM on-ground location, using the Fermi GBM trigger data, is consistent with IPN triangulation. The GBM light curve shows a complex structure, consisting of multiple peaks with a total duration (T90) of about 13.6 s (50-300 keV). The time-averaged spectrum from T0+1.024 s to T0+14.591 s is well fit by a power law function with an exponential high-energy cutoff. The power law index is -0.56 +/- 0.03 and the cutoff energy, parameterized as Epeak, is 270 +/- 6 keV. The event fluence (10-1000 keV) in this time interval is (2.3 +/- 0.3)E-05 erg/cm^2. The 1.024-sec peak photon flux measured starting from T0+11.20 s in the 10-1000 keV band is 13.6 +/- 0.4 ph/s/cm^2. The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog."