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GCN Circular 35511

GRB 240109B: Fermi GBM Final Real-time Localization
2024-01-09T21:41:29Z (4 months ago)
Fermi GBM Team at MSFC/Fermi-GBM <>
The Fermi GBM team reports the detection of a likely LONG GRB

At 21:30:52 UT on 9 Jan 2024, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 240109B (trigger 726528657.301666 / 240109896).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 241.5, Dec = -44.3 (J2000 degrees, equivalent to J2000 16h 06m, -44d 17'), with a statistical uncertainty of 12.2 degrees.

The angle from the Fermi LAT boresight is 91.0 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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