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GCN Circular 33839

GRB 230521A: Fermi GBM Final Real-time Localization
2023-05-21T05:13:46Z (a year ago)
Fermi GBM Team at MSFC/Fermi-GBM <>
The Fermi GBM team reports the detection of a likely SHORT GRB

At 05:03:23 UT on 21 May 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230521A (trigger 706338208.733194 / 230521211).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 37.0, Dec = 7.6 (J2000 degrees, equivalent to J2000 02h 28m, 7d 35'), with a statistical uncertainty of 7.8 degrees.

The angle from the Fermi LAT boresight is 54.0 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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