TITLE:   GCN CIRCULAR
NUMBER:  45525
SUBJECT: GRB 260907B: Fermi GBM Final Real-time Localization
DATE:    26/09/07 08:05:55 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 07:55:23 UT on 7 Sep 2026, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 260907B (trigger 810460528.709988 / 260907330).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 327.5, Dec = 24.9 (J2000 degrees, equivalent to J2000 21h 49m, 24d 53'), with a statistical uncertainty of 5.8 degrees.

The angle from the Fermi LAT boresight is 86.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260907330/quicklook/glg_skymap_all_bn260907330.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260907330/quicklook/glg_healpix_all_bn260907330.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260907330/quicklook/glg_lc_medres34_bn260907330.gif