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GCN Circular 29837

GRB 210420A: Fermi GBM Final Real-time Localization
2021-04-20T05:19:45Z (3 years ago)
Fermi GBM Team at MSFC/Fermi-GBM <>
The Fermi GBM team reports the detection of a likely LONG GRB

At 05:09:29 UT on 20 Apr 2021, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 210420A (trigger 640588174.204176 / 210420215).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 253.4, Dec = 12.2 (J2000 degrees, equivalent to J2000 16h 53m, 12d 11'), with a statistical uncertainty of 21.8 degrees.

The angle from the Fermi LAT boresight is 80.0 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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