Preliminary results on the muon reconstruction efficiency, momentum resolution, and momentum scale in ATLAS 2012 pp collision data

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 note summarizes the performance of the muon reconstruction algorithms and the data-driven techniques used for the measurements as derived from a dataset corresponding to an integrated luminosity of $20.4$~fb$^{-1}$ of $8$~TeV $pp$ collisions recorded in 2012. We also describe the corrections to be applied to simulation to reproduce the efficiency, momentum resolution and scale observed in experimental data. Finally, we introduce a method to determine the momentum uncertainty using the muon track fit uncertainty.