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GCN Circular 18664

GRB 151205A: Fermi GBM detection
2015-12-06T00:08:29Z (8 years ago)
Matthew Stanbro at UAH/Fermi <>
Matthew Stanbro (UAH) reports on behalf of the Fermi GBM Team:

"At 15:46:01.90 UT on 05 December 2015, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 151205A (trigger 471023165 / 151205657)
which was also detected by the Swift/BAT (Cummings et al. 2015, GCN 18657).
The GBM on-ground location is consistent with the Swift position.

The angle from the Fermi LAT boresight at the GBM trigger time is 76 degrees.

The GBM light curve consists of several episodes
with a duration (T90) of about 56 s (50-300 keV).
The time-averaged spectrum from T0-2.05 s to T0+55.30 s is
best fit by a power law function with an exponential
high-energy cutoff.  The power law index is 1.06 +/- 0.48 and
the cutoff energy, parameterized as Epeak, is 153 +/- 12 keV

The event fluence (10-1000 keV) in this time interval is
(2.56 +/- 0.21)E-06 erg/cm^2. The 1-sec peak photon flux measured
starting from T0-1.34 s in the 10-1000 keV band
is 1.36 +/- 0.15 ph/s/cm^2.

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

Matthew C. Stanbro
Fermi GBM Graduate Research Assistant
University of Alabama in Huntsville
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