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GCN Circular 33721

GRB 230503A: Fermi GBM Final Real-time Localization
2023-05-03T20:29:45Z (a year ago)
Fermi GBM Team at MSFC/Fermi-GBM <>
The Fermi GBM team reports the detection of a likely LONG GRB

At 20:19:07 UT on 3 May 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230503A (trigger 704837952.436878 / 230503847).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 66.0, Dec = -48.7 (J2000 degrees, equivalent to J2000 04h 24m, -48d 42'), with a statistical uncertainty of 2.9 degrees.

The angle from the Fermi LAT boresight is 72.0 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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