GCN Circular 21324
Subject
GRB 170711A: Fermi GBM observation
Date
2017-07-12T03:21:47Z (7 years ago)
From
Rachel Hamburg at UAH <rkh0007@uah.edu>
R. Hamburg (UAH) and C. Meegan (UAH)
report on behalf of the Fermi GBM Team:
"At 22:20:25.30 UT on 11 July 2017, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 170711A (trigger 521504430 / 170711931)
which was also detected by the Swift/BAT
(V. D'Elia et al. 2017, GCN 21321)
The GBM on-ground location is consistent with the Swift position.
The angle from the Fermi LAT boresight at the GBM trigger time is 32
degrees.
The GBM light curve shows one spike
with a duration (T90) of about 12 s (50-300 keV).
The time-averaged spectrum from T0-2.6 s to T0+10.8 s is
well fit by a power law function with an exponential
high-energy cutoff. The power law index is -1.5 +/- 0.1 and
the cutoff energy, parameterized as Epeak, is 155 +/- 34 keV.
The event fluence (10-1000 keV) in this time interval is
(2.6 +/- 0.2)E-06 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+0.3 s in the 10-1000 keV band
is 7.2 +/- 0.3 ph/s/cm^2.
The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog."