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GCN Circular 13595

GRB 120728A: Fermi GBM observation
2012-08-06T17:24:10Z (12 years ago)
Shaolin Xiong at UAH <>
Shaolin Xiong (UAH) reports on behalf of the Fermi GBM Team:

"At 22:25:13.737 UT on 28 July 2012, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 120728A (trigger 365207115 / 120728934)
which was also detected by the Swift/BAT (Cummings et al. 2012, GCN 13525).
The GBM on-ground location is consistent with the Swift position.

The angle from the Fermi LAT boresight is 110 degrees.

The GBM light curve consists of multiple pulses
with a duration (T90) of about 32.8 s (50-300 keV).
The time-averaged spectrum from T0-1.0 s to T0+23.6 s is
best fit by a power law function with an exponential
high-energy cutoff.  The power law index is -1.66 +/- 0.10 and
the cutoff energy, parameterized as Epeak, is 119.80 +/- 30.80 keV.

The event fluence (10-1000 keV) in this time interval is
(5.29 +/- 0.27)E-06 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+13.12 s in the 10-1000 keV band
is 3.58 +/- 0.28 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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