Muon identification and performance in the ATLAS experiment

Muon reconstruction and identification play a fundamental role in many analyses of central importance in the LHC run-2 Physics programme. The reconstruction and identification of muons with transverse momentum from a few GeV to the TeV scale at ATLAS, is presented. The performances are measured in data based on the decays of $Z$ and $J/\psi$ to pairs of muons, that provide a large statistics calibration sample. Reconstruction and identification efficiencies are evaluated, as well as momentum scales and resolutions, and the results are used to derive precise MC simulation corrections. Reconstruction efficiency also in presence of high pileup is presented