TITLE:   GCN CIRCULAR
NUMBER:  34571
SUBJECT: GRB 230826A: Fermi GBM Observation
DATE:    23/08/27 11:36:56 GMT
FROM:    rachel.hamburg@ijclab.in2p3.fr

O.J. Roberts (USRA) and C. Meegan (UAH) report on behalf of
the Fermi Gamma-ray Burst Monitor Team:

"At 19:32:44.53 UT on 26 August 2023, the Fermi Gamma-ray Burst Monitor (GBM)
triggered and located GRB 230826A (trigger 714771169/230826814),
which was also detected by Swift-BAT (R.A.J. Eyles-Ferris  et al. 2023, GCN 34565).
The Fermi GBM Final Real-time Localization (GCN 34564) is consistent with the Swift-BAT position.

The angle from the Fermi LAT boresight is 116 degrees.

The GBM light curve consists of a single FRED peak with a duration (T90)
of about 37 s (50-300 keV). The time-averaged spectrum
from T0-4.1 to T0+46.1 s is best fit by
a power law function with an exponential high-energy cutoff.
The power law index is -0.75 +/- 0.12 and the cutoff energy,
parameterized as Epeak, is 87 +/- 5 keV.

The event fluence (10-1000 keV) in this time interval is
(6.012 +/- 0.246)E-06 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+4.9 s in the 10-1000 keV band is 4.9 +/- 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/"