Sensitivity of ATLAS to alternative mechanisms of elektroweak symmetry breaking in vector boson scattering qq → qqlvlv [Elektronische Ressource] / von Jan W. Schumann. [Universität Bonn, Physikalisches Institut]

..UNIVERSITAT BONNPhysikalisches InstitutSensitivity of ATLAS to Alternative Mechanismsof Electroweak Symmetry Breaking in VectorBoson Scattering qq!qq‘ ‘ vonJan W. SchumacherAbstract An analysis of the expected sensitivity of the ATLAS experiment at theLarge Hadron Collider at CERN to alternative mechanisms of electroweak symmetrybreaking in the dileptonic vector boson scattering channel is presented. With thegeneralized K-Matrix model of vector boson scattering recently implemented in theevent generatorWhizard, several additional resonances are investigated. Whizardis validated for ATLAS use and an interface for the Les Houches event format isadapted for theA softwareAthena. Systematic model and statistical MonteCarlo uncertainties are reduced with a signal de nition using events reweighted in thecouplingsg of the new resonances. Angular correlations conserved by Whizard areused in the event selection. A multivariate analyzer is trained to take into accountcorrelations between the selection variables and thereby to improve the sensitivitycompared to cut analyses. The statistical analysis is implemented with a pro lelikelihood method taking into account systematic uncertainties and statistical uncer-tainties from Monte Carlo. Ensemble tests are performed to assure the applicability ofthe method. Expected discovery signi cances and coupling limits for new additionalresonances in vector boson scattering are determined.