GCN Circular 45162
Subject
GRB 260714B: Fermi-LAT detection
Event
Date
2026-07-15T02:59:59Z (4 days ago)
From
Rahul Gupta at NASA GSFC <rahul.gupta@nasa.gov>
Via
Web form
R. Gupta (NASA/GSFC), and N. Di Lalla (Stanford University) report on behalf of the Fermi-LAT collaboration:
At 18:23:26.76 UT on July 14th, 2026, Fermi-LAT detected high-energy emission from GRB 260714B, which was also detected by Fermi-GBM (trigger 805746211/260714766, GCN #45158).
The best LAT on-ground location is found to be
RA, Dec = 163.12, 46.98 (J2000)
with an error radius of 0.11 deg (90 % containment, statistical error only).
This was 57 deg from the LAT boresight at the time of the trigger.
The data from the Fermi-LAT show a significant increase in the event rate that is spatially and temporally correlated with the trigger with high significance.
The photon flux above 100 MeV in the time interval 0 - 400 s after the GBM trigger is (3.86 ± 0.91)E-5 ph/cm2/s. The estimated photon index above 100 MeV is -2.13 ± 0.23. The highest energy photon has an energy of 10 GeV and occurs at 200 s after trigger time.
The Fermi-LAT point of contact for this burst is Frédéric Piron (piron@in2p3.fr).
The Fermi-LAT is a pair conversion telescope designed to cover the energy band from 20 MeV to greater than 300 GeV. It is the product of an international collaboration between NASA and DOE in the U.S. and many scientific institutions across France, Italy, Japan and Sweden.