[vsnet-grb-info 23178] GRB 190805B: Fermi GBM detection

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  25277
SUBJECT: GRB 190805B: Fermi GBM detection
DATE:    19/08/05 21:16:24 GMT
FROM:    Rachel Hamburg at UAH  <rkh0007 at uah.edu>

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
(GBM)
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
degrees.

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:
https://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html

For Fermi GBM data and info, please visit the official Fermi GBM Support
Page:
https://fermi.gsfc.nasa.gov/ssc/data/access/gbm/"