GCN Circular 9346
V.Chaplin (UAH) reports on behalf of the Fermi GBM Team: "At 18:39:34.64 UT on 02 MAY 2009, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 090502 (trigger 262982376 / 090502777). The on-ground calculated location, using the GBM trigger data, is RA = 267.8, Dec = -20.3 (J2000 degrees, equivalent to J2000 17h 51m, -20d 18'), with a statistical uncertainty of 7.4 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 77 degrees. The GBM light curve shows a multi-peaked burst with a duration (T90) of about 66.2 s (8-1000 keV). The time-averaged spectrum from T0-11.6 to T0+62.1 s is best fit by a power-law with an exponential cut-off, with alpha = -1.1 +/- 0.3 and E-peak = 63.2 +/- 8.7 keV, (chi squared 227.86 for 241 d.o.f.) The fluence (8-1000 keV) in this time interval is (3.5 +/- 0.9)E-08 erg/cm^2. The 1-second peak photon flux starting from T0+37.5 is 6.2 +/- 0.9 ph/s-cm^2. The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog."