TITLE:   GCN CIRCULAR
NUMBER:  34531
SUBJECT: GRB 230822A: Fermi GBM Observation
DATE:    23/08/24 01:40:05 GMT
FROM:    Stephen Lesage at Fermi-GBM Team <sjl0014@uah.edu>

S. Lesage (UAH) and C. Meegan (UAH) report on behalf of
the Fermi Gamma-ray Burst Monitor Team:

"At 23:48:54 UT on 22 August 2023, the Fermi Gamma-ray Burst Monitor (GBM)
triggered and located GRB 230822A (trigger 714440939/230822992).
which was also detected by Swift/BAT-GUANO (DeLaunay et al. 2023, GCN 34529).
The Fermi GBM Final Real-Time Localization was reported previously (Fermi GBM Team 2023, GCN 34521).

The angle from the Fermi LAT boresight is 78 degrees.

The GBM light curve consists of a single weak emission episode with a duration (T90)
of about 0.9 s (50-300 keV). The time-averaged spectrum
from T0-0.448 to T0 s is best fit by
a simple power law function with index -1.3 +/- 0.2.

The event fluence (10-1000 keV) in this time interval is
(5.7 +/- 2.6)E-08 erg/cm^2. The 64-ms peak photon flux measured
starting from T0-1.7 s in the 10-1000 keV band is 2.2 +/- 0.9 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/"