Chapter 11: Higgs boson search in the WW → ℓℓvv and ℓℓqq final state

A Standard Model Higgs boson with a mass larger than 200 GeV decays almost exclusively to a pair of weak bosons. This chapter presents the search for such a high mass Higgs boson in the H → ZZ ℓℓqq and H → ZZ ℓℓvv final states performed by the ATLAS and CMS experiments. The search in these final states was instrumental in excluding a large range of Higgs boson masses beyond 200 GeV with the first few fb⁻¹ of integrated luminosity delivered by the LHC. This helped to narrow down the window for the Standard Model Higgs boson to masses around 100 GeV.