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GCN Circular 14545

GRB 130502A: Fermi GBM detection
2013-05-03T17:11:22Z (11 years ago)
George A. Younes at USRA/NASA/MSFC <>
G. Younes (NASA/USRA) reports on behalf of the Fermi GBM Team:

"At 17:50:30.74 UT on May 2 2013, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 130502A (trigger 389209833 / 130502743),
which was also detected by the Swift/BAT (Troja et al. 2013, GCN 14527).
The GBM on-ground location is consistent with the Swift position.

The angle from the Fermi LAT boresight is 20 degrees from Swift location.

The GBM light curve consists of a single pulse with a FRED-like shape
with a duration (T90) of about 3 s (50-300 keV).
The time-averaged spectrum from T0-0.384 s to T0+2.880 s is
well fit by a power law function with an exponential
high-energy cutoff.  The power law index is -1.0 +/- 0.3 and
the cutoff energy, parameterized as Epeak, is 83 +/- 17 keV.

The event fluence (10-1000 keV) in this time interval is
(5.0 +/- 0.6)E-07 erg/cm^2. The 0.064-sec peak photon flux measured
starting from T0-0.064 s in the 8-1000 keV band
is 7 +/- 1 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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