GCN Circular 9310
Sheila McBreen (UCD/MPE) reports on behalf of the Fermi GBM Team: "At 12:43:25.70 UT on 29 April 2009, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 090429C (trigger 262701807 / 090429530). The on-ground calculated location, using the GBM trigger data, is RA = 261.4, DEC = +55.5 (J2000 degrees, equivalent to 17 h 26 m, +55 d 30 '), with an uncertainty of 4.9 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 112 degrees. The GBM light curve consists of two pulses with a duration of about 13 s (8-1000 keV). The time-averaged spectrum from T0-2 s to T0+11 s is adequately fit by a simple power law function with index -1.43 +/- 0.04 (chi squared 513 for 471 d.o.f.). The event fluence (8-1000 keV) in this time interval is (3.7 +/- 0.1)E-6 erg/cm^2. The 0.256 sec peak photon flux measured starting from T0+0.768 s in the 8-1000 keV band is 6.7 +/- 0.4 ph/s/cm^2. The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog."