TITLE:   GCN CIRCULAR
NUMBER:  40529
SUBJECT: GRB 250522A: Fermi GBM Final Real-time Localization
DATE:    25/05/22 22:12:30 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM <do_not_reply@GIOC.nsstc.nasa.gov>

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

At 22:01:59 UT on 22 May 2025, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 250522A (trigger 769644124.77991 / 250522918).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 37.3, Dec = -5.4 (J2000 degrees, equivalent to J2000 02h 29m, -5d 24'), with a statistical uncertainty of 16.9 degrees.

The angle from the Fermi LAT boresight is 60.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250522918/quicklook/glg_skymap_all_bn250522918.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250522918/quicklook/glg_healpix_all_bn250522918.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250522918/quicklook/glg_lc_medres34_bn250522918.gif