TITLE: GCN CIRCULAR NUMBER: 14729 SUBJECT: GRB 130528A: Fermi GBM detection DATE: 13/05/30 15:42:30 GMT FROM: Peter Jenke at MSFC P. Jenke (UAH) reports on behalf of the Fermi GBM Team: "At 16:41:21.41 UT on May 28 2013, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 130528A (trigger 391452087 / 130528695), which was also detected by the Swift/BAT (D'Elia et al., GCN 14711). The GBM on-ground location is consistent with the Swift position. The angle of the Fermi LAT boresight is 60 degrees from the Swift location. The GBM light curve consists of at least three peaks with a duration (T90) of about 55 s (50-300 keV). The time-averaged spectrum from T0-0.9 s to T0+58.5 s is well fit by a power law function with an exponential high-energy cutoff. The power law index is -1.12 +/- 0.04 and the cutoff energy, parameterized as Epeak, is 130 +/- 7 keV. The event fluence (10-1000 keV) in this time interval is (9.5 +/- 0.3)E-06 erg/cm^2. The 1.0-sec peak photon flux measured starting from T0+3.2 s in the 10-1000 keV band is 5.5 +/- 0.2 ph/s/cm^2. The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog."