Aad, G.Abbott, B.Abdallah, J.Abdel Khalek, S.Abdinov, O.Aben, R.Abi, B.Izen, Joseph M.Leyton, MichaelLou, XinchouNamasivayam, HarisankarReeves, KendallATLAS Collaboration2015-09-242015-09-242015-03-132015-03-131434-6044http://hdl.handle.net/10735.1/4615The performance of the ATLAS muon trigger system is evaluated with proton-proton collision data collected in 2012 at the Large Hadron Collider at a centre-of-mass energy of 8 TeV. It is primarily evaluated using events containing a pair of muons from the decay of Z bosons. The efficiency of the single-muon trigger is measured for muons with transverse momentum 25 < p_T < 100 GeV, with a statistical uncertainty of less than 0.01% and a systematic uncertainty of 0.6%. The p_T range for efficiency determination is extended by using muons from decays of J/ψ mesons, W bosons, and top quarks. The muon trigger shows highly uniform and stable performance. The performance is compared to the prediction of a detailed simulation.;en-USCC BY 4.0 (Attribution)©2015 CERN, for the ATLAS Collaboration.http://creativecommons.org/licenses/by/4.0/J/ψ (J/psi) mesonProton-proton interactionsW bosonsZ bosonsMuonsTransverse momentumTextAad, G., B. Abbott, J. Abdallah, S. Abdel Khalek, et al. 2015. "Performance of the ATLAS muon trigger in pp collisions at √s = 8 TeV." European Physical Journal C, Particles and Fields 75(120): doi:10.1140/epjc/s10052-015-3325-9.753