GCN Circular 25469
Subject
GRB 190824A: Fermi GBM observation
Date
2019-08-24T22:06:37Z (5 years ago)
From
Cori Fletcher at USRA <cfletcher@usra.edu>
C. Fletcher (USRA) and C. Meegan (UAH)
report on behalf of the Fermi GBM Team:
"At 14:46:37.67 UT on 24 August 2019, the Fermi Gamma-Ray Burst Monitor (GBM)
triggered and located GRB 190824A (trigger 588350802 / 190824616),
which was also detected by the Swift/BAT (D'Elia et al. 2019, GCN 25463)
The Fermi GBM Final Real-time Localization (GCN 25462) is consistent with the Swift position.
The angle from the Fermi LAT boresight at the GBM trigger time is 82 degrees.
The GBM light curve consists of an initial bright pulse followed by
multiple peaks with a duration (T90) of about 109 s (50-300 keV).
The time-averaged spectrum from T0-1.024 s to T0+107.52 s is
best fit by a power law function with an exponential
high-energy cutoff. The power law index is -1.38 +/- 0.06 and
the cutoff energy, parameterized as Epeak, is 247 +/- 55 keV
The event fluence (10-1000 keV) in this time interval is
(1.4 +/- 0.1)E-05 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+2.05 s in the 10-1000 keV band
is 7.9 +/- 0.4 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/"