TITLE:   GCN CIRCULAR
NUMBER:  46224
SUBJECT: GRB 261111A: Fermi GBM Final Real-time Localization
DATE:    26/11/11 11:37:41 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 11:27:07 UT on 11 Nov 2026, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 261111A (trigger 816089232.948464 / 261111477).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 56.9, Dec = 5.8 (J2000 degrees, equivalent to J2000 03h 47m, 5d 47'), with a statistical uncertainty of 2.0 degrees.

The angle from the Fermi LAT boresight is 58.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn261111477/quicklook/glg_skymap_all_bn261111477.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/bn261111477/quicklook/glg_healpix_all_bn261111477.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn261111477/quicklook/glg_lc_medres34_bn261111477.gif