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GCN Circular 34197

GRB 230707B: Fermi GBM Observation
2023-07-10T20:00:51Z (10 months ago)
S. Bala (USRA) and C. Meegan (UAH) report on behalf of
the Fermi Gamma-ray Burst Monitor Team:

"At 18:46:20.29 UT on 07 July 2023, the Fermi Gamma-ray Burst Monitor (GBM)
triggered and located GRB 230707B (trigger 710448385/230707782).
which was also detected by Swift/BAT-GUANO (James DeLaunay et al. 2023, GCN 34169)
and CALET GBM (S. Torii et al. 2023, GCN 34189). The Fermi GBM Final Real-time Localization
was reported at GCN 34165.

The angle from the Fermi LAT boresight is 83 degrees.

The GBM light curve is long and consists of many peaks with a duration (T90)
of 99.6 s (50-300 keV). The time-averaged spectrum
from T0-2.3 to T0+117.5 s is best fit by
a Band function with Epeak = 143 +/- 5 keV,
alpha = -0.63 +/- 0.04, and beta = -2.15 +/- 0.05.

The event fluence (10-1000 keV) in this time interval is
(5.4 +/- 0.1)E-05 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+80 s in the 10-1000 keV band is 5.3 +/- 0.3 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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