TITLE: GCN CIRCULAR NUMBER: 12412 SUBJECT: GRB 111003A: Fermi GBM detection DATE: 11/10/04 19:04:14 GMT FROM: Gerard Fitzpatrick at UCD G. Fitzpatrick (UCD) reports on behalf of the Fermi GBM Team: At 11:10:00.23 UT on 03 October 2011, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 111003A (trigger 339333002/111003465). The on-ground calculated location, using the GBM trigger data, is RA = 276.8 , DEC = -62.3 (J2000 degrees, equivalent to 18 h 27 m, -62 d 18.0'), with an uncertainty of 1.1 degrees (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 62.00 degrees. Moreover, this burst was bright enough to result in a Fermi spacecraft repointing maneuver. The GBM light curve consists of two peaks with a duration (T90) of 17 s (50-300 keV). The time-averaged spectrum from T0-1.0 s to T0+17.9 s is well fit by a power law function with an exponential high-energy cutoff. The power law index is -0.94 (+/- 0.02) and the cutoff energy, parameterized as Epeak, is 231.5 (+/- 8.0) keV. The event fluence (10-1000 keV) in this time interval is (1.83 +/- 0.03)E-05 erg/cm^2. The 1-sec peak photon flux measured starting from T0+3.6 s in the 10-1000 keV band is 18.2 +/- 0.5 ph/s/cm^2. The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog.