Tree-level Interference in VBF production of $Vh$

TL;DR

This paper investigates the VBF production of Higgs with a vector boson, highlighting how tree-level interference effects can reveal deviations in Higgs couplings at the HL-LHC and future colliders.

Contribution

It demonstrates the sensitivity of the VBF-VH process to Higgs coupling deviations, especially in scenarios with opposite sign couplings, using interference effects.

Findings

Interference effects can distinguish Higgs coupling signs.

VBF-VH process is sensitive to deviations in Higgs couplings.

Future colliders can probe coupling scenarios difficult to detect otherwise.

Abstract

We study the production of the Higgs in a association with a vector ($V=W,Z$) via the VBF process, VBF-VH. In the Standard Model (SM), this process exhibits tree-level destructive interference between between $W$ and $Z$ mediated processes and is thus very sensitive to deviations in Higgs couplings to vector bosons. We study this process at both the HL-LHC as well as future high energy lepton colliders. We show in particular that the scenario where Higgs couplings have the same magnitude but opposite relative sign as in the SM, a scenario that is very difficult to distinguish without interference, can be probed with this process at either collider.