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GCN Circular 34754

GRB 230921A: Fermi GBM Final Real-time Localization
2023-09-21T02:51:55Z (9 months ago)
Fermi GBM Team at MSFC/Fermi-GBM <>
The Fermi GBM team reports the detection of a likely LONG GRB

At 02:41:32 UT on 21 Sep 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230921A (trigger 716956897.615146 / 230921112).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 239.4, Dec = -33.4 (J2000 degrees, equivalent to J2000 15h 57m, -33d 23'), with a statistical uncertainty of 6.9 degrees.

The angle from the Fermi LAT boresight is 39.0 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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