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GCN Circular 17308

GRB 150118B: Fermi GBM Detection
2015-01-18T23:44:36Z (10 years ago)
Matthew Stanbro at UAH/Fermi <>
Matthew Stanbro (UAH) reports on behalf of the Fermi GBM Team:

"At 09:48:17.77 UT on 18 January 2015, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 150118B (trigger 443267300 / 150118409)
which was also detected by the Fermi-LAT (Kocevski et al. 2015, GCN 17307)
The GBM on-ground location is consistent with the LAT position.
The trigger caused GBM to generate an Autonomous Repoint of Fermi.

The GBM light curve consists of several episodes
with a duration (T90) of about 40 s (50-300 keV).
The time-averaged spectrum from T0-4.608 s to T0+49.665 s is
best fit by a power law function with an exponential
high-energy cutoff.  The power law index is -0.89 +/- 0.01 and
the cutoff energy, parameterized as Epeak, is 755 +/- 14 keV

The event fluence (10-1000 keV) in this time interval is
(1.5 +/- 0.007)E-04 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+45.8 s in the 8-1000 keV band
is 40.7 +/- 0.4 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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