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GCN Circular 25277

GRB 190805B: Fermi GBM detection
2019-08-05T21:16:24Z (5 years ago)
Rachel Hamburg at UAH <>
R. Hamburg (UAH) and C. Meegan (UAH)
report on behalf of the Fermi GBM Team:

"At 04:46:00.97 UT on 05 August 2019, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 190805B (trigger 586673165 / 190805199),
which was also detected by the MAXI/GSC (Sato et al. 2019, GCN 25271).
The Fermi GBM Final Real-time Localization (GCN 25270) is consistent with
the MAXI position.

The angle from the Fermi LAT boresight at the GBM trigger time is 46

The GBM light curve shows a spiky, multi-peaked structure with a
duration (T90) of about 22 s (50-300 keV). The time-averaged
spectrum from T0-4.6 s to T0+ 25.1 s is best fit by a power law function
with an exponential high-energy cutoff. The power law index
is -1.07 +/- 0.05 and the cutoff energy, parameterized as Epeak,
is 389 +/- 51 keV.

The event fluence (10-1000 keV) in this time interval is
(1.03 +/- 0.05)E-05 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+16 s in the 10-1000 keV band
is 7.6 +/- 0.3 ph/s/cm^2.

The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog:

For Fermi GBM data and info, please visit the official Fermi GBM Support
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