GCN Circular 17094
Subject
GRB 141118A: Fermi GBM Detection
Date
2014-11-24T17:54:58Z (9 years ago)
From
Peter Jenke at MSFC <peter.a.jenke@nasa.gov>
P. Jenke (UAH) reports on behalf of the Fermi GBM Team:
"At 16:15:50.31 on November 18 2014, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 141118A (trigger 438020153/141118678).
The GBM on-ground location, using the Fermi GBM trigger
data, is RA = 158.1, Dec = 19.8 (J2000 degrees, equivalent to
10h 32m 24s, 19d 48'), with an uncertainty of 2.2
degrees (radius, 1-sigma containment,statistical
only; there is additionally a systematic error which is
currently estimated to be 2 to 3 degrees).
GBM's location is consistent with the IPN
Triangulation (K. Hurley et al. 2014, GCN 17073).
This GRB was also detected by Konus-Wind (Golenetskii et al. GCN 17074).
A follow-up search of GBM's error box by iPTF
produced an optical candidate, well within
the GBM 1 sigma confidence region, that on further
investigations turned out to be a fading SNe unrelated
to the GRB (Singer et al. 2014, GCN 17079).
The angle of the burst direction to the Fermi LAT boresight is
74 degrees.
The GBM light curve consists of a single peak with a duration
(T90) of about 4.4 s (50-300 keV).
The time-averaged spectrum from T0-2.9 s to T0+3.2s
is well fit by a power law function with an exponential
high-energy cutoff. The power law index is -0.77 +/- 0.09
and the cutoff energy, parameterized as Epeak, is 286 +/- 34 keV.
The event fluence (10-1000 keV) in this time interval is
(3.3 +/- 0.2)E-06 erg/cm^2. The 1 sec peak photon flux measured
starting from T0+0.0 s in the 10-1000 keV band
is 6.5 +/- 0.3 ph/s/cm^2.
The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog."