GCN Circular 17328
Subject
GRB 150118C: Fermi GBM Detection
Date
2015-01-20T22:28:31Z (10 years ago)
From
Eric Burns at U of Alabama <eb0016@uah.edu>
E. Burns (UAH) report on behalf of the Fermi GBM Team:
"At 22:14:32.66 UT on 18 January 2015, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 150118C (trigger 443312075 / 150118927).
The GBM on-ground location is consistent with the IPN location
(K. Hurley et al. 2015, GCN 17324). The angle from the Fermi LAT
boresight is 92 degrees.
The GBM light curve consists of a single pulse
with a duration (T90) of about 0.3 s (50-300 keV).
The time-averaged spectrum from T0-0.128 s to T0+0.320 s is
best fit by a power law function with an exponential
high-energy cutoff. The power law index is -1.1 +/- 0.1 and
the cutoff energy, parameterized as Epeak, is 658 +/- 143 keV.
It is equally well fit by a Band function with
Epeak = 415 +/- 117 keV, alpha = -0.9 +/- 0.1, and
beta = -2.0 +/- 0.2.
The event fluence (10-1000 keV) in this time interval is
(1.2 +/- 0.1)E-06 erg/cm^2. The 64-ms peak photon flux measured
starting from T0+0.00 s in the 10-1000 keV band
is 39.6 +/- 2.0 ph/s/cm^2.
The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog."