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GCN Circular 15687

GRB 140104B: Fermi GBM observation
2014-01-05T18:42:56Z (10 years ago)
Shaolin Xiong at UAH <>
Shaolin Xiong (UAH) reports on behalf of the Fermi GBM Team:

"At 17:32:03.15 UT on 04 January 2014, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 140104B (trigger 410549526 / 140104731),
which was also detected by the ground analysis of Fermi/LAT
(Vianello et al. 2014, GCN 15684)
The GBM on-ground location is consistent with the LAT position.

The GBM light curve consists of multiple pulses
with a duration (T90) of about 190 s (50-300 keV).
The time-averaged spectrum from T0 to T0+200 s is
well fit by a power law function with an exponential
high-energy cutoff. The power law index is -1.23 +/- 0.06 and
the cutoff energy, parameterized as Epeak, is 280 +/- 40 keV.

The event fluence (10-1000 keV) in this time interval is
(3.2 +/- 0.2)E-5 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+190.7 s in the 10-1000 keV band
is 5.7 +/- 0.2 ph/s/cm^2.

The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog."
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