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TITLE:   GCN CIRCULAR
NUMBER:  31777
SUBJECT: GRB 220321A: Fermi GBM Final Localization
DATE:    22/03/21 15:44:33 GMT
FROM:    Joshua Wood at MSFC/Fermi-GBM  <joshua.r.wood@nasa.gov>

The Fermi GBM team reports the detection of a likely SHORT GRB

At 06:46:22.00 UT on 21 Mar 2022, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 220321A (trigger 669537987 / 220321282).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 170.8, Dec = 28.9 (J2000 degrees, equivalent to J2000 11h 23m, +28d 54'), with a statistical uncertainty of 8.6 degrees.

The angle from the Fermi LAT boresight is 57.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220321282/quicklook/glg_skymap_all_bn220321282.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/bn220321282/quicklook/glg_healpix_all_bn220321282.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220321282/quicklook/glg_lc_medres34_bn220321282.gif