TITLE: GCN CIRCULAR NUMBER: 13785 SUBJECT: GRB 120919A: Fermi GBM detection DATE: 12/09/20 11:02:08 GMT FROM: Arne Rau at MPE Arne Rau (MPE) reports on behalf of the Fermi GBM Team: "At 07:24:41.98 UT on 19 September 2012, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 120919A (trigger 369732284 / 120919309). The on-ground calculated location, using the GBM trigger data, is RA = 213.4, DEC = -46.3 (J2000 degrees, equivalent to 14 h 14 m, -46 d 18 '), 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 63 degrees. Moreover, this burst was bright enough to result in a Fermi spacecraft autonomous re-point request (ARR) maneuver. This burst was also independently detected by INTEGRAL SPI-ACS. The GBM light curve shows a single bright pulse with a duration (T90) of about 22.5 s (50-300 keV). The time-averaged spectrum from T0+0.003 s to T0+10.496 s is best fit by a Band function with Epeak = 162 +/- 8 keV, alpha = -0.76 +/- 0.04, and beta = -2.15 +/- 0.06 The event fluence (10-1000 keV) in this time interval is (1.679 +/- 0.026)E-05 erg/cm^2. The 1.024-sec peak photon flux measured starting from T0+2.62 s in the 10-1000 keV band is 25.3 +/- 0.3 ph/s/cm^2. The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog." [GCN OPS NOTE(20sep12): Per author's request, the fluence value was changed from "(1.60 +/- 0.03)E-06" to "(1.679 +/- 0.026)E-05".]