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GCN Circular 32900

GRB 221029A: Fermi GBM Final Localization
2022-10-31T13:42:50Z (a year ago)
Joe Mangan at UCD <>
The Fermi GBM team reports the detection of a likely Long GRB.

"At 01:05:27.31 UT on 29 October 2022, the Fermi Gamma-Ray Burst
Monitor (GBM) triggered and located GRB221029A (trigger 688698332 /

The on-ground calculated location, using the GBM trigger data, is RA =
53.3, DEC = -44.9 (J2000 degrees, equivalent to 3h 33m, -44d 54'),
with a statistical uncertainty of 1 degrees (radius, 1-sigma
containment, statistical only; there is additionally a systematic
error which we have characterized as a core-plus-tail model, with 90%
of GRBs having a 3.7 deg error and a small tail suffering a larger
than 10 deg systematic error. [Connaughton et al. 2015, ApJS, 216, 32]

The angle from the Fermi LAT boresight at the GBM trigger time is 72 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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