GCN Circular 30499

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

At 14:46:07 UT on 23 July 2021, the Fermi Gamma-ray Burst Monitor (GBM)
triggered and located GRB 210723A (trigger 648744372/210723615).
which was also detected by Swift BAT (T. Sbarrato et al. 2021, GCN 30485
Not found
 
 
)
The Fermi GBM on-ground location is consistent with the Swift BAT position.

The angle from the Fermi LAT boresight is 94 degrees.

The GBM light curve consists of a single emission episode with a duration
(T90)
of about 43 s (10-1000 keV). The time-averaged spectrum
from T0+1.5 to T0+36.4 s is best fit by
a power law function with an exponential high-energy cutoff.
The power law index is -0.67 +/- 0.07 and the cutoff energy,
parameterized as Epeak, is 113 +/- 5 keV.

The event fluence (10-1000 keV) in this time interval is
(7.6 +/- 0.2)E-06 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+1 s in the 10-1000 keV band is 4.7 +/- 0.3 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/"