TITLE:   GCN CIRCULAR
NUMBER:  42455
SUBJECT: GRB 251026B: Fermi GBM Final Localization
DATE:    25/10/26 09:48:27 GMT
FROM:    Marianna Dafčíková at Masaryk University <500025@mail.muni.cz>

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

"At 07:18:53.33 UT on 26 October 2025, the Fermi Gamma-ray Burst Monitor (GBM)
triggered and located GRB 251026B (trigger 783155938/251026305).

The on-ground calculated location, using the Fermi GBM trigger data,
is RA = 132.32, Dec = -12.21 (J2000 degrees, equivalent to J2000 8h 49m, -12d 12'),
with a statistical uncertainty of 8.04 degrees.

The angle from the Fermi LAT boresight is 19 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn251026305/quicklook/glg_skymap_all_bn251026305.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/bn251026305/quicklook/glg_healpix_all_bn251026305.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn251026305/quicklook/glg_lc_medres34_bn251026305.gif"