GCN Circular 44859

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

"At 13:19:28.70 UT on 07 June 2026, the Fermi Gamma-ray Burst Monitor (GBM)
triggered and located GRB 260607B (trigger 802531173/260607555).
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 = 55.11, Dec = 26.90 (J2000 degrees, equivalent to J2000 +03h 40m, +26d 54'),
with a statistical uncertainty of 1.00 degree.

The angle from the Fermi LAT boresight is 68 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260607555/quicklook/glg_skymap_all_bn260607555.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/bn260607555/quicklook/glg_healpix_all_bn260607555.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260607555/quicklook/glg_lc_medres34_bn260607555.gif"