GCN Circular 31011
Subject
GRB 211024A: Fermi GBM detection
Date
2021-10-26T22:38:14Z (3 years ago)
From
Suraj Poolakkil at UAH <sp0076@uah.edu>
S. Poolakkil (UAH) and C. Meegan (UAH)
report on behalf of the Fermi GBM Team:
"At 01:34:11.40 UT on 24 October 2021, the Fermi Gamma-Ray Burst Monitor
(GBM)
triggered and located GRB 211024A (trigger 656732056 / 211024065)
which was also detected by the Swift/BAT-GUANO (Tohuvavohu et al. 2021, GCN
31006).
The GBM on-ground location is consistent with the Swift/BAT-GUANO position.
The angle from the Fermi LAT boresight at the GBM trigger time is 119
degrees.
The GBM light curve consists of a single emission episode
with a duration (T90) of about 0.06 s (50-300 keV).
The time-averaged spectrum from T0-0.128 s to T0+0.128 s
is best fit by a power law function with an exponential
high-energy cutoff. The power law index is -0.23 +/- 0.39 and
the cutoff energy, parameterized as Epeak, is 145 +/- 27 keV.
The event fluence (10-1000 keV) in this time interval is
(1.95 +/- 0.28)E-07 erg/cm^2. The 64-ms peak photon flux measured
starting from T0 s in the 10-1000 keV band
is 10.4 +/- 1.4 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/"