Search for resonant WZ to lv ll production using 13 fb-1 in center of mass energy = 8 TeV p-p collisions with the ATLAS detector

This dissertation presents a search for a resonant state decaying to a W and a Z boson using events with three charged leptons (electrons or muons) and missing transverse energy. The search is performed using proton-proton collisions at a center-of-mass energy of 8 TeV, produced by the LHC and measured by the ATLAS detector in 2012. This data sample corresponds to an integrated luminosity of 13.0 fb -1. Events are selected with reconstructed W and Z bosons found at similar rapidity and large angular separation. The invariant mass of three leptons and missing energy is calculated, assuming on-shell W production, and compared to the Standard Model expectation. No significant excess is observed and the results are interpreted as cross-section times branching ratio limits for two specific models. In the context of an Extended Gauge Model, a W&feet; boson is excluded at a 95 % confidence level for masses below 1180 GeV. In the context of a Low Scale Technicolor model, two- dimensional limits are set for values of the technipion and technirho mass between 200 GeV and 1000 GeV. These limits are generalizable to any model predicting a narrow resonance that decays to a W and a Z boson.