Search for Higgs boson production at high transverse momentum in the WW decay channel in proton-proton collisions at $ \sqrt{s} = $ 13 TeV
A search for Higgs boson (H) production at high transverse momentum ($ p_{\mathrm{T}} $) in the WW decay channel is presented. The analysis uses proton-proton collisions at $ \sqrt{s}= $ 13 TeV recorded by the CMS experiment in 2016--2018, corresponding to an integrated luminosity of 138 fb$ ^{-1} $. The visible decay products of the Higgs boson are reconstructed as a single large-radius jet with one isolated lepton or none (1 $ \ell $ and 0 $ \ell $, respectively; $ \ell=\mathrm{e},\mu $). The H-candidate jets are identified using an advanced transformer-based algorithm and are calibrated with the Lund jet plane reweighting technique. The 1 $ \ell $ channel is further split into gluon fusion, vector boson fusion, and associated production with hadronically decaying vector boson categories, while the 0 $ \ell $ channel considers all production processes inclusively. The measured cross section times the $ \mathrm{H} \to \mathrm{W} \mathrm{W} $ branching fraction relative to the standard model expectation is $ \mu = - $ 0.19 $ ^{+0.48}_{-0.46} $, indicating no evidence of a signal above the background. This measurement represents the first dedicated study of highly Lorentz-boosted $ \mathrm{H} \to \mathrm{W} \mathrm{W} $ decays, complementing earlier searches for high-$ p_{\mathrm{T}} $ Higgs boson in other decay channels.




