TITLE:   GCN CIRCULAR
NUMBER:  45286
SUBJECT: GRB 260805A: Fermi GBM Final Localization
DATE:    26/08/05 11:02:33 GMT
FROM:    Marianna Dafčíková at Masaryk University <500025@mail.muni.cz>

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

"At 09:18:33.28 UT on 05 August 2026, the Fermi Gamma-ray Burst Monitor (GBM)
triggered and located GRB 260805A (trigger 807614318/260805388).
This trigger was initially classified as Distant Particles by the flight software,
but is in fact a GRB.

The on-ground calculated location, using the Fermi GBM trigger data,
is RA = 252.53, Dec = 34.93 (J2000 degrees, equivalent to J2000 16h 50m, +34d 56'),
with a statistical uncertainty of 3.11 degrees.

The angle from the Fermi LAT boresight is 112 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260805388/quicklook/glg_skymap_all_bn260805388.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/bn260805388/quicklook/glg_healpix_all_bn260805388.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260805388/quicklook/glg_lc_medres34_bn260805388.gif"