TITLE: GCN CIRCULAR NUMBER: 14839 SUBJECT: GRB 130609A: Fermi GBM observation DATE: 13/06/09 20:20:46 GMT FROM: Gerard Fitzpatrick at UCD G. Fitzpatrick (UCD) and J. Michael Burgess (UAH) report on behalf of the Fermi GBM Team: At 03:05:10.69 UT on 09 June 2013, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 130609A (trigger 392439913 /130609129), which was also detected by the Swift/BAT (Cummings et al., GCN Circ. 14828). The GBM on-ground location is consistent with the Swift position. The GBM light curve consists of a single peak with a duration (T90) of about 5 s (50-300 keV). The time-averaged spectrum from T0-2.6 s to T0+2.8 s is adequately fit by a power law function with an exponential high-energy cutoff. The power law index is -1.2 +/- 0.2 and the cutoff energy, parameterized as Epeak, is 59.5 +/- 7.3 keV. The event fluence (10-1000 keV) in this time interval is (7.7 +/- 0.6)E-07 erg/cm^2. The 1-sec peak photon flux measured starting from T0-1.6 s in the 8-1000 keV band is 3.2 +/- 0.3 ph/s/cm^2. The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog.