GCN Circular 17353
Matthew Stanbro (UAH) reports on behalf of the Fermi GBM Team: "At 20:50:35.78 UT on 26 January 2015, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 150126A (trigger 443998238 / 15012686) which MAXI detected an afterglow candidate (Takagi et al. 2015, GCN 17352). The GBM on-ground location is consistent with MAXI position. The angle from the Fermi LAT boresight is 92 degrees. The GBM light curve consists of 2 main episodes with a duration (T90) of about 97 s (50-300 keV). The time-averaged spectrum from T0-2.05 s to T0+91.14 s is best fit by a Band function with Epeak = 217 +/- 17 keV, alpha = -1.07 +/- 0.04, and beta = -2.45 +/- 0.22 The event fluence (10-1000 keV) in this time interval is (2.55 +/- 0.06)E-05 erg/cm^2. The 1-sec peak photon flux measured starting from T0+71.3 s in the 10-1000 keV band is 9.71 +/- 0.36 ph/s/cm^2. A power law function with an exponential high-energy cutoff fits the spectrum equally well. The power law index is -1.11 +/- 0.03 and the cutoff energy, parameterized as Epeak, is 240 +/- 13 keV. The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog."