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GCN Circular 34613

GRB 230904A: Fermi GBM Final Real-time Localization
2023-09-04T08:30:14Z (9 months ago)
Fermi GBM Team at MSFC/Fermi-GBM <>
The Fermi GBM team reports the detection of a likely SHORT GRB

At 08:19:31 UT on 4 Sep 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230904A (trigger 715508376.33399 / 230904347).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 278.5, Dec = -20.8 (J2000 degrees, equivalent to J2000 18h 33m, -20d 48'), with a statistical uncertainty of 21.7 degrees.

The angle from the Fermi LAT boresight is 74.0 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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