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GCN Circular 33700

GRB 230428A: Fermi GBM Final Real-time Localization
2023-04-28T09:19:35Z (a year ago)
Fermi GBM Team at MSFC/Fermi-GBM <>
The Fermi GBM team reports the detection of a likely LONG GRB

At 09:08:58 UT on 28 Apr 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230428A (trigger 704365743.150826 / 230428381).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 121.8, Dec = -86.1 (J2000 degrees, equivalent to J2000 08h 07m, -86d 05'), with a statistical uncertainty of 15.9 degrees.

The angle from the Fermi LAT boresight is 30.0 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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