TITLE:   GCN CIRCULAR
NUMBER:  30490
SUBJECT: GRB 210722A: Fermi GBM observation
DATE:    21/07/23 21:29:26 GMT
FROM:    Joshua Wood at MSFC/Fermi-GBM  <joshua.r.wood@nasa.gov>

J. Wood (NASA/MSFC)
reports on behalf of the Fermi GBM Team:

"At 20:54:40.87 UT on 22 July 2021, the Fermi Gamma-Ray Burst Monitor (GBM)
triggered and located GRB 210722A (trigger 648680085 / 210722871)
which was also detected by the Swift/BAT and Swift/XRT (P. D'Avanzo et al. 2021, GCN 30475).

The GBM on-ground location is consistent with the Swift position.

The GBM light curve consists of a single peak
with a duration (T90) of about 62 s (50-300 keV).
The time-averaged spectrum from T0-1.5 s to T0+62 s is
well fit by a power law function with an exponential
high-energy cutoff.  The power law index is -1.1 +/- 0.1 and
the cutoff energy, parameterized as Epeak, is 160 +/- 30 keV

The event fluence (10-1000 keV) in this time interval is
(5.8 +/- 0.6)E-06 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+2.3 s in the 10-1000 keV band
is 4.0 +/- 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/"