Speaker
Description
A search for Higgs boson pair production via vector-boson fusion is performed in the Lorentz-boosted regime, where a Higgs boson candidate is reconstructed as a single large-radius jet, using $140\ \mathrm{fb}^{-1}$ of proton--proton collision data at $\sqrt{s}=13\ \mathrm{TeV}$ recorded by the ATLAS detector at the Large Hadron Collider. Only Higgs boson decays into bottom-quark pairs are considered. The search is particularly sensitive to the quartic coupling between two vector bosons and two Higgs bosons relative to its Standard-Model prediction, $\kappa_{2V}$. This study constrains $\kappa_{2V}$ to $0.55<\kappa_{2V}<1.49$ at the $95\%$ confidence level. The value $\kappa_{2V}=0$ is excluded with a significance of $3.8$ standard deviations with other Higgs-boson couplings fixed to their Standard-Model values. A search for new heavy spin-0 resonances that would mediate Higgs-boson pair production via vector-boson fusion is carried out in the mass range of $1$-$5\ \mathrm{TeV}$ for the first time under several model and decay-width assumptions. No significant deviation from the Standard-Model hypothesis is observed and exclusion limits at the $95\%$ confidence level are derived.
Phys. Lett. B 858 (2024) 139007
