TITLE: GCN CIRCULAR NUMBER: 8824 SUBJECT: GRB 090117B : Fermi GBM detection DATE: 09/01/18 12:31:04 GMT FROM: Andreas von Kienlin at MPE Andreas von Kienlin (MPE) reports on behalf of the Fermi GBM Team: "At 08:02:02.23 UT on 17 January 2009, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 090117B (trigger 253872124 / 090117335) The on-ground calculated location, using the GBM trigger data, is RA = 232.9, DEC = 27.6 (J2000 degrees, equivalent to 15h 32m, 27d 36'), with an uncertainty of 9.4 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 49 degrees The GBM light curve consists of two separate peaks, the first from T0-0.768 to T0+0.768 sec and the second from T0+24.0643 sec to T0+26.368 sec. T90 (8-1000 keV) is about 27 sec. Both peaks were fit using a power-law function with index -1.55 +/- 0.08 (chi squared 272.27/245 d.o.f.) for the first and with index -1.55 +/- 0.07 (chi squared 249.72/245 d.o.f.)for the second peak. The event fluence (8-1000 keV) for both peaks is (2.1 +/- 0.1)E-06 erg/cm^2. The 1-sec peak photon flux measured starting from T0-0.768 s in the 8-1000 keV band is 4.6 +/- 0.2 ph/s/cm^2 The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog."