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GCN Circular 31392

GRB 220104A: Fermi GBM Observation
2022-01-05T20:14:11Z (2 years ago)
Boyan A. Hristov at UAH <>
Boyan A. Hristov (MPE/UAH) reports on behalf of the
Fermi GBM Team:

"At 04:01:02.60 UT on 04 January 2022, the Fermi Gamma-Ray
Burst Monitor (GBM) triggered and located GRB 220104A
(trigger 662961667 / 220104167) which was also detected by
GECAM (Z. W. Guo et al. 2022, GCN 31382).

The GBM on-ground location (GCN 31380) is consistent with the
GECAM position.

The GBM light curve consists of multiple peaks with a duration
(T90) of about 2.624 s (50-300 keV).  The time-averaged
spectrum from T0-0.128 s to T0+0.320 s is best fit by a simple
power law function with index -1.28 +/- 0.05.

The event fluence (10-1000 keV) in this time interval is
(3.5 +/- 0.34)E-07 erg/cm^2.
The 64-miliseconds peak photon flux measured starting from
T0-0.064 s in the 10-1000 keV band
is 4.00 +/- 0.98 ph/s/cm^2.

The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog:

For Fermi GBM data and info, please visit the official Fermi
GBM Support Page:"
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