Study of Vector Boson Scattering with Pile-up with the ATLAS Detector at the LHC

Effects of physics beyond the Higgs-less Standard Model are expected in the vector boson scattering channel. The chiral electroweak Lagrangian extended by additional resonances and unitarized with the K-matrix model can parametrize these effects. An analysis of the sensitivity of the ATLAS experiment at the Large Hadron Collider at CERN to these resonances is presented. Especially the effects of additional proton- proton interactions per bunch crossing (pile-up) are investigated. A training and evaluation of a multivariate analyzer is performed and used to determine ranges of sensitivity for couplings of the resonances. Systematic uncertainties are taken into account.