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GCN Circular 35170

GRB 231123B: Fermi GBM Final Real-time Localization
2023-11-23T19:35:41Z (8 months ago)
Fermi GBM Team at MSFC/Fermi-GBM <>
The Fermi GBM team reports the detection of a likely LONG GRB

At 19:25:21 UT on 23 Nov 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 231123B (trigger 722460326.50637 / 231123809).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 160.4, Dec = -68.9 (J2000 degrees, equivalent to J2000 10h 41m, -68d 54'), with a statistical uncertainty of 6.1 degrees.

The angle from the Fermi LAT boresight is 104.0 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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