TITLE: GCN CIRCULAR NUMBER: 17146 SUBJECT: GRB 141207A: Fermi-LAT Detection DATE: 14/12/08 06:29:49 GMT FROM: Daniel Kocevski at GSFC M. Arimoto (Tokyo Tech), D. Kocevski (NASA/GSFC), R. Desiante (INFN Trieste & Udine University), and M. Axelsson (KTH Royal Institute of Technology, Sweden) report on behalf of the Fermi-LAT team: At 19:11:21.10 on December 7, 2014, Fermi-LAT detected high-energy emission from GRB 141207A, which was also detected by Fermi-GBM (trigger 439672284/141207800). The best LAT on-ground location is found to be (RA, Dec.) = 159.99, +3.91 deg with an error radius of 0.215 deg (90% containment, statistical error only). This position was 59 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 within 2 degree of the GBM location after the GBM trigger that is spatially and temporally correlated with the GBM emission with high significance. More than 27 photons above 100 MeV and more than 6 photons above 1 GeV are observed within 100 seconds. The highest-energy photon is a ~5 GeV event which is observed ~750 seconds 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 (arimoto@hp.phys.titech.ac.jp). 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.