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GCN Circular 19769

GRB 160804A: Fermi GBM observation
2016-08-04T21:54:43Z (8 years ago)
Rachel Hamburg at UAH <>
E. Bissaldi (Politecnico & INFN Bari), C. M. Hui (MSFC),
V. Connaughton (USRA), and Rachel Hamburg (UAH)
report on behalf of the Fermi GBM Team:

"At 01:34:16.04 UT on 04 August 2016, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 160804A (trigger 491967260 / 160804065),
which was also detected by the Swift-BAT (Marshall et al. 2016, GCN 19761).
The GBM on-ground location is consistent with the Swift position.

The angle from the Fermi LAT boresight at the GBM trigger time is 87

The GBM light curve consists of single emission episode
with a duration (T90) of about 130 s (50-300 keV).
The time-averaged spectrum from T0-60 s to T0+70 s is
best fit by a power law function with an exponential
high-energy cutoff.  The power law index is -1.1 +/- 0.1 and
the cutoff energy, parameterized as Epeak, is 74 +/- 3 keV.

The event fluence (10-1000 keV) in this time interval is
(1.5 +/- 0.3)E-05 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+10 s in the 10-1000 keV band
is 4.6 +/- 0.3 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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