GCN Circular 17971
M. Arimoto (Tokyo Tech), J.E. McEnery (NASA/GSFC), F. Longo (Trieste) and M. Axelsson (KTH Stockholm) report on behalf of the Fermi-LAT team: At 04:23:23.68 UT on June 27, 2015, Fermi-LAT detected high-energy emission from GRB 150627A, which was also detected by Fermi-GBM (trigger 457071806/ 150627183). The best LAT on-ground location is found to be RA, Dec = 117.49, -51.56 (J2000) with an error radius of 0.05 deg (90 per cent containment, statistical error only). This was 75 deg from the LAT boresight at the time of the trigger and triggered an autonomous repoint of the spacecraft. 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 highest-energy photon is a 8.1 GeV event which is observed 259 s after the GBM trigger. A Swift ToO has been requested for this burst. The Fermi-LAT point of contact for this burst is Makoto Arimoto (email@example.com) 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.