Evidence for Electroweak Production of W±W±jj in Proton-Proton Collisions at vs = 8 TeV with the ATLAS Detector at the LHC.

Abstract

This thesis presents the first study of the same-electric-charge WWjj production using 20.3/fb of proton-proton collision data at a center-of-mass energy of 8 TeV recorded by the ATLAS detector at the LHC during the year of 2012. Only the leptonic decays of both W's are considered. Events are selected with two same-electric-charge leptons (ee, emu, mumu) and at least two hadronic jets. The inclusive and electroweak productions of WWjj are studied in two fiducial signal regions and the production cross sections are measured. First evidence for inclusive and electroweak production is observed with a significance of 4.5 and 3.6 standard deviations respectively. The measured production cross sections are in agreement with the Standard Model predictions. First set of constraints on the anomalous WWWW quartic gauge couplings are derived.