First measurements of vector boson scattering in W±W± and WZ production in all-leptonic final states at √s=13.6 TeV

A bstract The production cross sections of W ± W ± and WZ boson pairs in association with two jets in proton-proton collisions are measured at √s=13.6 s = 13.6 TeV. The data sample corresponds to an integrated luminosity of 171 fb − 1 , collected with the CMS detector during 2022–2024. The measurements are performed in the leptonic decay modes: W ± Z → ℓ ± νℓ′ ± ℓ′ ∓ and W ± W ± → ℓ ± νℓ′ ± ν , where ℓ , ℓ′ = e or μ . The electroweak productions of W ± W ± and WZ bosons are each observed with a significance greater than five standard deviations from the background-only hypothesis. Differential fiducial cross sections as functions of several observables are also measured.