TITLE:   GCN CIRCULAR
NUMBER:  45943
SUBJECT: GRB 261013A: Fermi GBM Final Real-time Localization
DATE:    26/10/13 14:08:22 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 SHORT GRB

At 13:57:44 UT on 13 Oct 2026, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 261013A (trigger 813592669.12119 / 261013582).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 138.6, Dec = 17.6 (J2000 degrees, equivalent to J2000 09h 14m, 17d 36'), with a statistical uncertainty of 15.4 degrees.

The angle from the Fermi LAT boresight is 97.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn261013582/quicklook/glg_skymap_all_bn261013582.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/bn261013582/quicklook/glg_healpix_all_bn261013582.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn261013582/quicklook/glg_lc_medres34_bn261013582.gif