Multi-Higgs Production and Unitarity in Vector-Boson Fusion at Future Hadron Colliders

Understand

We study multi-Higgs final states in vector boson fusion (VBF) processes at the LHC and at future proton-proton colliders, focusing on the prospects for measurements at 27 TeV and at 100 TeV.

• We use an effective Lagrangian which includes higher-dimensional operators in the mass eigenstates which are relevant to VBF processes and relate this to specific parameterizations and models for new physics in the Higgs sector.
• We derive theoretical constraints on the parameter space from the unitarity of $2\to n$ scattering amplitudes and apply the results to $V V \to hh$ and $h h h$ processes, where $V=W,Z$.
• As a result, we present constraints on differential distributions as appropriate to the study of $V V \to hh$ and $h h h$ processes.