GCN Circular 31710
Subject
GRB 220304A Fermi GBM detection
Event
Date
2022-03-08T16:11:39Z (5 years ago)
From
Boyan A. Hristov at UAH <bah0046@uah.edu>
Boyan A. Hristov (UAH) and C. Meegan (UAH) report on behalf of
the Fermi GBM Team:
"At 05:28:58.79 UT on 04 March 2022, the Fermi Gamma-Ray Burst
Monitor (GBM) triggered and located GRB 220304A (trigger
668064543 / 220304228, GCN 31672), which was also detected by
the Swift/BAT-GUANO (DeLaunay et al. 2022, GCN 31677).
The GBM light curve consists of a single spike with a duration
(T90) of about 32 s (50-300 keV). The time-averaged spectrum
from T0+3.072 s to T0+35.841 s is best fit by a Band function
with Epeak = 90 +/- 2 keV, alpha = -0.24 +/- 0.06, and beta =
-3.2 +/- 0.1. The event fluence (10-1000 keV) in this time
interval is (59 +/- 0.7)E-6 erg/cm^2. The 1-sec peak photon
flux measured starting from T0+15.488 s in the 10-1000 keV band
is 36 +/- 1 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/"