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GCN Circular 29183

GRB 201228A: Fermi GBM Final Real-time Localization
2020-12-28T02:37:48Z (3 years ago)
Fermi GBM Team at MSFC/Fermi-GBM <>
The Fermi GBM team reports the detection of a likely LONG GRB

At 02:27:30 UT on 28 Dec 2020, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 201228A (trigger 630815255.731822 / 201228102).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 303.4, Dec = 32.3 (J2000 degrees, equivalent to J2000 20h 13m, 32d 17'), with a statistical uncertainty of 15.4 degrees.

The angle from the Fermi LAT boresight is 44.0 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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