TITLE: GCN CIRCULAR NUMBER: 9347 SUBJECT: GRB 090510B: Fermi GBM detection DATE: 09/05/11 16:02:42 GMT FROM: Arne Rau at MPE Arne Rau (MPE) reports on behalf of the Fermi GBM Team: "At 07:47:39.51 UT on 10 May 2009, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 090510B (trigger 263634461 / 090510325). The on-ground calculated location, using the GBM trigger data, is RA = 269.4 , DEC = -57.9 (J2000 degrees, equivalent to 17h 57m, -57d 56'), with an uncertainty of 11.6 degrees (radius, 1-sigma containment, statistical only; there is additionally a systematic error which is currently estimated to be 2 to 3 degrees). The GBM light curve shows a single peak with a duration (T90) of about 7s (8-1000 keV). The angle from the Fermi LAT boresight is 100 degrees. Since the source is weak, the time-averaged spectrum is poorly constrained."