TITLE: GCN CIRCULAR NUMBER: 19879 SUBJECT: GRB 160829A: Fermi-LAT detection of a short GRB DATE: 16/08/29 17:28:47 GMT FROM: Judith Racusin at GSFC J. L. Racusin (NASA/GSFC), G. Vianello (Stanford), D. Kocevski (NASA/GSFC), E. Bissaldi (Politecnico & INFN Bari), and R. Desiante (INFN Torino) report on behalf of the Fermi-LAT team: At 08:01:37 on August 29, 2016 Fermi-LAT detected high-energy emission from GRB 160829A, which was also detected by Fermi-GBM (trigger 494150501/160829334). The best LAT on-ground location is found to be RA, Dec = 201.7, -56.77 (degrees, J2000) with an error radius of 0.12 deg (90% containment, statistical error only). This was 11 deg from the LAT boresight at the time of the trigger. The data from the Fermi-LAT show an increase in the event rate within 10 deg of the GBM location after the GBM trigger that is spatially and temporally correlated with the GBM emission. The highest-energy photon is a 9.5 GeV event which is observed ~2 seconds after the GBM trigger, and the GRB is otherwise relatively faint, with only 3 photons (>100 MeV) with a >90% probability of being associated with the burst. A Swift ToO has been requested for this burst. The Fermi-LAT point of contact for this burst is Judith Racusin (judith.racusin@nasa.gov). 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.