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GCN Circular 33600

GRB 230409C: Fermi GBM Final Real-time Localization
2023-04-09T22:38:23Z (a year ago)
Fermi GBM Team at MSFC/Fermi-GBM <>
The Fermi GBM team reports the detection of a likely LONG GRB

At 22:27:45 UT on 9 Apr 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230409C (trigger 702772070.370746 / 230409936).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 195.9, Dec = -53.4 (J2000 degrees, equivalent to J2000 13h 03m, -53d 23'), with a statistical uncertainty of 10.5 degrees.

The angle from the Fermi LAT boresight is 86.0 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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