%0 Thesis %A Roy, Dennis Mario %T Search for a high mass Higgs boson decaying into two W bosons in the dileptonic final state with CMS %I RWTH Aachen University %V Dissertation %C Aachen %M RWTH-2023-00530 %P 1 Online-Ressource : Illustrationen %D 2022 %Z Veröffentlicht auf dem Publikationsserver der RWTH Aachen University 2023 %Z Dissertation, RWTH Aachen University, 2022 %X A search is performed for an additional Higgs boson decaying into a pair of W bosons in the fully leptonic final state. The analysis uses data from proton-proton collisions recorded by the Compact Muon Solenoid experiment at the Large Hadron Collider. Data were recorded in 2016, 2017 and 2018 and correspond to an integrated luminosity of 138 fb^-1. New techniques are implemented in the analysis to improve the sensitivity of the search, especially in the mass range above 1 TeV. In one of the considered scenarios, a local excess in data is observed at a mass of 650 GeV with a global significance of 2.6 σ. The results of the analysis include 95 %F PUB:(DE-HGF)11 %9 Dissertation / PhD Thesis %R 10.18154/RWTH-2023-00530 %U https://publications.rwth-aachen.de/record/862521