GCN Circular 8505
Subject
GRB 081109: Fermi GBM detection
Date
2008-11-09T15:56:47Z (16 years ago)
From
Andreas von Kienlin at MPE <azk@mpe.mpg.de>
A. von Kienlin (MPE) reports on behalf of the Fermi GBM Team:
"At 07:02:02.42 UT on 09 November 2008, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 081109 (trigger 247906923 / 081109293), which was
also detected by the SWIFT (S. Immler et al. 2008, GCN 8500).
The GBM on-ground location is consistent with the Swift position.
The GBM light curve shows a single peak
with a duration (T90) of about 45 s (8-1000 keV).
The time-averaged spectrum from T0-6.144 s to T0+26.624 s is
best fit by a power law function with an exponential
high energy cutoff. The power law index is -1.28 +/- 0.09 and
the cutoff energy, parameterized as Epeak is 240 +/- 60 keV.
(chi squared 510 for 478 d.o.f.)
The event fluence (8-1000 keV) in this time interval is
(6.53 +/- 0.43)E-06 erg/cm^2. The 1-sec photon flux measured
starting from T0+9.216 s in the 8-1000 keV band
is 3.2 +/- 0.3 ph/s/cm^2.
The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog."