TITLE: GCN CIRCULAR NUMBER: 8214 SUBJECT: GRB 080906B: Fermi GBM detection DATE: 08/09/11 16:01:22 GMT FROM: Elisabetta Bissaldi at MPE E. Bissaldi, S. McBreen and A. von Kienlin (MPE) report on behalf of the Fermi GBM Team: "At 05:05:11 UT on 6 September 2008, the Fermi Gamma-ray Burst Monitor triggered and located GRB 080906B (trigger 242370312 / 080906212). The on-ground calculated location, using the Fermi GBM trigger data, is RA = 185.5, Dec = -8.6 (J2000 degrees) (equivalent to J2000 12h 22m, -08d 36'), with a statistical uncertainty of 3.3 degrees (radius, 1-sigma containment; there is additionally a systematic error which is currently estimated to be 2 to 3 degrees). The angle from the Fermi LAT boresight is 32 degrees. This GRB consists of one main emission phase comprising several overlapping pulses, with an estimated T90 (50-300 keV) of about 5 s. The time-averaged spectrum from T0 to T0+3.8 s is best fit by a Band function with the following parameters: alpha = -0.07 +/- 0.09 beta = -2.10 +/- 0.07 Epeak = 125.3 +/- 6.6 keV The fluence (25-1000 keV) is 10.9 (+/-0.1)E-06 erg/cm2. The peak flux (25-1000 keV) on the 128 ms timescale is 22 +/- 4 ph/s/cm2. The spectral analysis results presented above are preliminary; the final results will be published in the Fermi GBM GRB Catalog."