GCN Circular 17813
Younes G. (USRA at GWU) and Meegan C. (UAH) report on behalf of the Fermi GBM Team: "At 20:33:15.25 UT, on 2015 May 13, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 150513A (trigger 453241998 / 150513856) which was also detected by Swift (Kocevski et al. 2015, GCN 17810) and Fermi/LAT (Kocevski et al. 2015, GCN 17812). The GBM on-ground location is consistent with the Swift position. The angle from the Fermi LAT boresight is about 45 degrees. The GBM light curve shows two peaks separated by about 150 s with a duration (T90) of 165 s (50-300 keV). The time-averaged spectrum from T0-161.5 s to T0+4.3 s is well fit by a BAND function with Epeak = 252 +/- 63 keV, alpha = -0.9 +/- 0.1, and beta = -1.69 +/- 0.06. The event fluence (10-1000 keV) in this time interval is (1.36 +/- 0.04)E-05 erg/cm^2. The 1 second peak photon flux measured starting from T0+0.2 s in the 10-1000 keV band is 4.1 +/- 0.3 ph/s/cm^2. The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog."