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GCN Circular 32903

GRB 221029A: Fermi GBM observation
2022-11-01T13:34:55Z (a year ago)
Joe Mangan at UCD <>
J. Mangan (UCD), R. Dunwoody (UCD) and C. Meegan (UAH), report on behalf of
the Fermi GBM Team:

At 01:05:27.31 UT on 29 October 2022, the Fermi Gamma-Ray Burst Monitor (GBM)
triggered and located GRB 221029A (trigger 688698332 / 21029045). The
Fermi GBM Final Real-time Localization is reported in GCN 32900.

The GBM light curve consists of three emission episodes
with a duration (T90) of about 27.7 s (50-300 keV).
The time-averaged spectrum from T0+0.003 s to T0+28.416 s is
best fit by a Band function with Epeak = 130.7 +/- 6.3 keV,
alpha = -1.12 +/- 0.03, and beta = -2.15 +/- 0.04

The event fluence (10-1000 keV) in this time interval is
(2.69 +/- 0.04)E-05 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+0.32 s in the 10-1000 keV band
is 35.5 +/- 0.5 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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