GCN Circular 32495

P. Veres and C. Meegan (both UAH)
report on behalf of the Fermi GBM Team:

"At 11:55:22.98 UT on 26 August 2022, the Fermi Gamma-Ray Burst Monitor
(GBM)
triggered and located GRB 220826A (trigger 220826497 / 683207727)
which was also detected by the Swift/BAT (Caputo et al., GCN 32484
Not found
 
 
)
The GBM on-ground location is consistent with the Swift position.

The angle from the Fermi LAT boresight at the GBM trigger time is 54
degrees.

The GBM light curve shows  two pulses
with a duration (T90) of about 16.6 s (50-300 keV).
The time-averaged spectrum from T0-0.5 s to T0+10.8 s is
best fit by a power law function with an exponential
high-energy cutoff.  The power law index is -0.66 +/- 0.20 and
the cutoff energy, parameterized as Epeak, is 113 +/- 14 keV

The event fluence (10-1000 keV) in this time interval is
(1.50 +/- 0.14)E-6 erg/cm^2. The 1-sec peak photon flux measured
starting from T0 + 5.2 s in the 10-1000 keV band
is 4.3 +/- 0.3 ph/s/cm^2.

A Band function fits the spectrum equally well
with Epeak= 66 +/- 13 keV, alpha = 0.28 +/- 0.58 and beta = -2.14 +/- 0.18.

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/"