  The ATLAS experiment identifies and reconstructs muons with two high
precision tracking systems, the Inner Detector and the Muon Spectrometer, which
provide independent measurements of the muon momentum. This paper summarizes
the performance of the combined muon reconstruction in terms of reconstruction
efficiency, momentum scale and resolution. Data-driven techniques are used to
derive corrections to be applied to the simulation in order to reproduce the
reconstruction efficiency, momentum scale and resolution observed in
experimental data, and to assess systematic uncertainties on these quantities.
The dataset analysed corresponds to an integrated luminosity of $20.4$
$\text{fb}^{\text{-1}}$ from $pp$ collisions at $\sqrt{s}$ = 8 TeV recorded in
2012.
