Performance of Tau Identification and Associated Systematic Uncertainties in ATLAS

In these proceedings, a description of the reconstruction and identification methods for tau leptons in ATLAS at the LHC is presented. Identifying tau leptons is essential in many analyses, be it Standard Model (SM) and Higgs boson signatures or searches for physics beyond the SM. The decay of the tau particle with leptonic as well as hadronic decay modes and its short lifetime makes it especially challenging to identify and measure this lepton. After a short introduction about the tau lepton and its reconstruction in ATLAS, three different identification methods are presented in more detail. The identification efficiencies and their systematic uncertainties are summarized as measured in the 2010 data analysis in ATLAS.