Survey of Higgs interpretations of the diboson excesses

TL;DR

This paper explores how extended Higgs sectors could explain the diboson excesses observed at the LHC, analyzing unitarity sum-rules, proposing a two-Higgs-doublet model, and discussing experimental constraints and correlations with SM Higgs signals.

Contribution

It provides a detailed analysis of Higgs interpretations of diboson excesses using unitarity sum-rules and proposes a specific two-Higgs-doublet model consistent with experimental data.

Findings

A 2 TeV CP-even Higgs can explain diboson signals.

Constraints from LHC searches limit the model parameters.

Precise SM Higgs measurements are crucial for testing the interpretation.

Abstract

We investigate diboson signals in the Standard Model (SM) with an extended Higgs sector, motivated by the excesses in the diboson channels at the LHC. We begin with the unitarity sum-rules of the weak gauge boson scattering assuming the Higgs sector is extended. According to the sum-rules, we discuss the Higgs interpretations of the diboson signals and the consistency with the ATLAS diboson anomaly and other experimental constraints. As a concrete example, we propose a two-Higgs-doublet model where the Yukawa coupling of an extra CP-even scalar with up-type quark is relatively large. The diboson (WW and ZZ) signals can be explained by 2 TeV CP-even Higgs boson, while the partners, the CP-odd and the charged Higgs bosons in the extra doublet, are severely constrained by both the LHC direct search and the indirect search via flavor observables. Especially, in order to avoid the diboson resonance search in the Vh channel, further extensions of the model are required. The diboson excess is correlated with the SM Higgs signals in our framework, so that the precise measurement of the SM Higgs boson is also important to test the Higgs interpretation.