TITLE: GCN CIRCULAR NUMBER: 22081 SUBJECT: GRB 171102A: Fermi-LAT detection DATE: 17/11/02 15:00:44 GMT FROM: Manal Yassine at INFN,Trieste **M. Yassine (Univ & INFN Trieste), E. Bissaldi (Politecnico & INFN Bari) and D. Kocevski (NASA/MSFC) report on behalf of the Fermi-LAT team: At 2:33:35.99 UT on November 02, 2017, Fermi-LAT detected high-energy emission from GRB 171102A, which was also detected by Fermi-GBM (trigger 531282820). The best LAT on-ground location is found to be RA, Dec: 188.41, 53.63 (degrees, J2000) with an error radius of 0.57 deg (90% containment, statistical error only). This was 43 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 GBM emission with high significance. More than 17 photons above 100 MeV are observed within 500 seconds. The highest-energy photon is a 500 MeV event which is observed 328 seconds after the GBM trigger. A Swift ToO has been requested for this burst. The Fermi-LAT point of contact for this burst is Manal Yassine (mychbib@gmail.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. [GCN OPS NOTE(03nov17): Per author's request, the URL link to the Swift ToO page and the URL link to gmail were removed.] [GCN OPS NOTE(06nov17): Per author's request, intitutional affiliation was corrected from INAF to INFN.]