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GCN Circular 30873

Retraction of Fermi GBM GRB 210923A: the trigger is not a GRB
2021-09-23T22:03:59Z (3 years ago)
Joe Mangan at UCD <>
J.Mangan (UCD), S.Lesage (UAH) report on behalf of the Fermi Gamma-ray
Burst Monitor Team:

The Fermi Gamma-ray Burst Monitor (GBM) trigger 654090581/210923493 at
11:49:36.820 UT
on 23 September 2021, tentatively classified as a GRB (GCN 30865), is in
fact not due
to a GRB. This trigger is likely due to a terrestrial electron beam (TEB).
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