A search for high-mass resonances in final states with hadronically decaying tau leptons and high missing transverse momentum using <em>pp</em>-colision data at √<em>s</em> = 13 TeV collected by the ATLAS Detector

Abstract

A search for new heavy charged gauge bosons <em>W'</em>, predicted by some extensions of the Standard Model is presented in this thesis. This analysis is based on data collected from proton-proton collisions with a center-of-mass-energy of √<em>s</em> = 13 TeV by the ATLAS detector. The integrated luminosity corresponds to 139 fb⁻¹. The search is performed in the decay channel with one tau lepton that decays hadronically and a neutrino, <em>W'</em> → τν. The scenarios considered are the <em>Sequential Standard Model</em>, where the <em>W'</em>-bosons have the same couplings as the Standard Model <em>W</em>-bosons, as well as <em>Non-Universal Gauge Interaction Models</em>, which allow for preferential couplings to the heavy generation of fermions. <br/> No significant excess is observed in data and upper limits at 95% confidence level on the production cross sections of the <em>W'</em> bosons under the different signal hypotheses. Model-independent upper limits are also derived to allow re-interpretation of the results in more generic models.