Tau Reconstruction and Identification Performance at ATLAS

For many signals in the Standard Model and new physics like Supersymmetry and Higgs Bosons, $ au$ leptons represent an important signature. This work shows the performance of the ATLAS $ au$ reconstruction and identification algorithms with the first 7 TeV data. It will present a set of studies based on data taken in 2010 at a center-of-mass energy of $sqrt{s}$ = 7 TeV. We measured some of the basic input quantities used for this identification methods from selected reconstructed $ au$ candidates and compared the results to the prediction of different Monte Carlo simulation models. For early data taking a cut-based identification method will be used. We also measured the background efficiency for cut-based $ au$ identification.