GCN Circular 32594

The Fermi GBM team reports the detection of a likely Long GRB.

"At 05:36:20.95 UT on 27 September 2022, the Fermi Gamma-Ray Burst Monitor
(GBM) triggered and located GRB220927A (trigger 685949785 / 220927234).

The on-ground calculated location, using the GBM trigger data, is RA =
96.2, DEC = -22.5 (J2000 degrees, equivalent to 6h 24m, -22d 30'), 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 57
degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220927234/quicklook/glg_skymap_all_bn220927234.png

The HEALPix FITS file, including the estimated localization systematic, can
be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220927234/quicklook/glg_healpix_all_bn220927234.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220927234/quicklook/glg_lc_medres34_bn220927234.gif