GCN Circular 16900
Subject
GRB 141004A: Fermi GBM observation
Date
2014-10-06T19:47:12Z (10 years ago)
From
Veronique Pelassa at UAH <vero.pelassa@gmail.com>
V. Pelassa (UAH) reports on behalf of the Fermi GBM Team:
"At 23:20:54.42 UT on 4 October 2014, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 141004A (trigger 434157657 / 141004973),
which was also detected by the Swift/BAT (D'Elia et al. 2014, GCN 16878)
and the INTEGRAL/IBIS (Mereghetti et al 2014, GCN 16879).
The GBM on-ground location is consistent with the Integral position, which
lies at an angle of 100.4 degrees from the Fermi LAT boresight.
The GBM light curve consists of a short FRED peak followed by a faint tail
with a duration (T90) of about 3 s (50-300 keV).
The time-averaged spectrum from T0-0.320 s to T0+0.768 s (main peak) is
best fit by a power law function with an exponential
high-energy cutoff. The power law index is -1.3 +/- 0.1 and
the cutoff energy, parameterized as Epeak, is 147 +/- 28 keV
(Castor stat 398.59 for 365 d.o.f.).
The event fluence (10-1000 keV) in this time interval is
(2.2 +/- 0.2)E-06 erg/cm^2. The 64-msec peak photon flux measured
starting from T0+0.000 s in the 10-1000 keV band
is 18 +/- 2 ph/s/cm^2.
The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog."