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GCN Circular 33035

GRB 221209B: Fermi GBM Final Real-time Localization
2022-12-09T21:13:45Z (a year ago)
Fermi GBM Team at MSFC/Fermi-GBM <>
The Fermi GBM team reports the detection of a likely LONG GRB

At 21:03:27 UT on 9 Dec 2022, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 221209B (trigger 692312612.788022 / 221209877).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 142.1, Dec = -5.2 (J2000 degrees, equivalent to J2000 09h 28m, -5d 12'), with a statistical uncertainty of 10.6 degrees.

The angle from the Fermi LAT boresight is 92.0 degrees.

The skymap can be found here:

The HEALPix FITS file, including the estimated localization systematic, can be found here:

The GBM light curve can be found here:
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