TITLE:   GCN CIRCULAR
NUMBER:  41964
SUBJECT: GRB 250924B: Fermi GBM Final Localization
DATE:    25/09/24 13:25:19 GMT
FROM:    Padraig McDermott at University College Dublin <padraig.mcdermott@ucdconnect.ie>

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

"At 10:26:58.90 UT on 24 September 2025, the Fermi Gamma-ray Burst Monitor (GBM)
triggered and located GRB250924B (trigger 780402423/250924435).

The on-ground calculated location, using the Fermi GBM trigger data,
is RA = 306.44, Dec = -61.82 (J2000 degrees, equivalent to J2000 20h 25m, -61d 49'),
with a statistical uncertainty of 9.50 degrees.

The angle from the Fermi LAT boresight is 150 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250924435/quicklook/glg_skymap_all_bn250924435.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/bn250924435/quicklook/glg_healpix_all_bn250924435.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250924435/quicklook/glg_lc_medres34_bn250924435.gif"