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GCN Circular 34478

GRB 230818A: Fermi GBM Final Real-time Localization
2023-08-18T23:38:02Z (a year ago)
Fermi GBM Team at MSFC/Fermi-GBM <>
The Fermi GBM team reports the detection of a likely LONG GRB

At 23:27:35 UT on 18 Aug 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230818A (trigger 714094060.372856 / 230818977).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 289.2, Dec = 41.0 (J2000 degrees, equivalent to J2000 19h 16m, 41d 00'), with a statistical uncertainty of 2.7 degrees.

The angle from the Fermi LAT boresight is 79.0 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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