TITLE:   GCN CIRCULAR
NUMBER:  39430
SUBJECT: GRB 250223A: Fermi GBM Final Real-time Localization
DATE:    25/02/23 16:46:39 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 16:36:11 UT on 23 Feb 2025, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 250223A (trigger 762021376.807148 / 250223692).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 340.6, Dec = -40.3 (J2000 degrees, equivalent to J2000 22h 42m, -40d 17'), with a statistical uncertainty of 31.6 degrees.

The angle from the Fermi LAT boresight is 95.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250223692/quicklook/glg_skymap_all_bn250223692.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/bn250223692/quicklook/glg_healpix_all_bn250223692.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250223692/quicklook/glg_lc_medres34_bn250223692.gif