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GCN Circular 33490

GRB 230321A: Fermi GBM Final Real-time Localization
2023-03-21T04:32:02Z (6 months ago)
Fermi GBM Team at MSFC/Fermi-GBM <>
The Fermi GBM team reports the detection of a likely LONG GRB

At 04:21:43 UT on 21 Mar 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230321A (trigger 701065308.721614 / 230321182).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 74.8, Dec = 28.0 (J2000 degrees, equivalent to J2000 04h 59m, 28d 00'), with a statistical uncertainty of 6.2 degrees.

The angle from the Fermi LAT boresight is 53.0 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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