TITLE: GCN CIRCULAR NUMBER: 10944 SUBJECT: GRB 100707A: Fermi GBM detection DATE: 10/07/07 18:44:31 GMT FROM: Colleen A. Wilson at NASA/MSFC/NSSTC Colleen A. Wilson-Hodge (NASA/MSFC) and Suzanne Foley (MPE) report on behalf of the Fermi GBM Team: "At 00:46:38.99 UT on 07 July 2010, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 100707 (trigger 300156400 / 100707.032). The on-ground calculated location, using the GBM trigger data, is RA = 351.07, DEC = -6.57 (J2000 degrees, equivalent to 23 h 24 m, -6 d 34 '), with an uncertainty of 1 degree (radius, 1-sigma containment, statistical only; there is additionally a systematic error which is currently estimated to be 2 to 3 degrees). The angle from the Fermi LAT boresight is 90 degrees. The GBM light curve show a fast rise and exponential decay with a duration (T90) of 82+/-1 s (50-300 keV). The time-averaged spectrum from T0-0.064 s to T0+83.009 s is well fit by a power law function with an exponential high energy cutoff. The power law index is -0.91 +/- 0.02 and the cutoff energy, parameterized as Epeak, is 283 +/- 7 keV (C-Statistic 529.4 for 358 d.o.f.). The event fluence (10-1000 keV) in this time interval is (8.77 +/- 0.02)E-05 erg/cm^2. The 1-sec peak photon flux measured starting from T0+1.152 s in the 10-1000 keV band is 48.3 +/- 0.4 ph/s/cm^2. The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog."