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GCN Circular 15923

GRB 140304A: Fermi GBM detection
2014-03-04T22:27:39Z (10 years ago)
Peter Jenke at MSFC <>
P. Jenke (UAH) and G. Fitzpatrick (UCD) reports on behalf of the Fermi GBM Team:

"At 13:22:31.48 UT on March 4 2014, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 140304A (trigger 415632154/140304577),
which was also detected by Swift (P. A. Evans et al. 2014, GCN 15915).  
The GBM on-ground location, using the Fermi GBM trigger
data, is consistent with the Swift/XRT location.

The angle of the burst direction to the Fermi LAT boresight is 80 degrees.

The GBM light curve consists of two main peaks with a
combined duration (T90) of 32 +/- 6 s (50-300 keV).
The time-averaged spectrum from T0-5 s to T0+14 s is
well fit by a power law function with an exponential
 high energy cutoff. The power law index is -1.1 +/- 0.1 
and the high energy cutoff, parameterized as 
EPeak, is 185 +/- 35 keV.

The event fluence (10-1000 keV) in this time interval is
(2.6 +/- 0.2)E-06 erg/cm^2. The 1.0-sec peak photon flux measured
starting from T0+7.2 s in the 10-1000 keV band
is 2.5 +/- 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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