TITLE:   GCN CIRCULAR
NUMBER:  31702
SUBJECT: GRB 220306B: Fermi GBM observation
DATE:    22/03/07 01:20:35 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 18:15:36.24 UT on 06 March 2022, the Fermi Gamma-Ray Burst Monitor (GBM)
triggered and located GRB 220306B (trigger 668283341 / 220306761)
which was also detected by the Swift/BAT and Swift/XRT (Caputo et al. 2022, GCN 31697).
The GBM on-ground location is consistent with the Swift position.

The GBM light curve consists of a single pulse
with a duration (T90) of about 10.2 s (50-300 keV).
The time-averaged spectrum from T0-1.0 s to T0+9.2 s is
best fit by a Band function with Epeak = 160 +/- 122 keV,
alpha = -1.1 +/- 0.3, and beta = -1.8 +/- 0.2

The event fluence (10-1000 keV) in this time interval is
(1.7 +/- 0.2)E-06 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+1.2 s in the 10-1000 keV band
is 2.8 +/- 0.2 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/"