TITLE:   GCN CIRCULAR
NUMBER:  42826
SUBJECT: GRB 251124A: Fermi GBM Localization by automated pipeline
DATE:    25/11/24 17:34:45 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 LONG GRB

At 12:58:03 UT on 24 Nov 2025, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 251124a (trigger 785681888.46989 / 251124540), which has also been reported in GCN 42820. An interruption in the automated pipeline caused the automated circular to be distributed later than normal.

The on-ground automated localization is consistent with the location in GCN 42820.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn251124540/quicklook/glg_skymap_all_bn251124540.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/bn251124540/quicklook/glg_healpix_all_bn251124540.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn251124540/quicklook/glg_lc_medres34_bn251124540.gif