Little Higgs Model Discrimination at the LHC and ILC

TL;DR

This paper proposes a method to distinguish between two types of Little Higgs models at future colliders by exploiting a unique coupling of pseudoaxions to the Z and Higgs bosons, observable at the LHC and ILC.

Contribution

It introduces a novel collider-based approach to differentiate Little Higgs model variants using pseudoaxion couplings, applicable at both LHC and ILC.

Findings

Pseudoaxion coupling enables model discrimination at the LHC.

Resonant production of Higgs or pseudoaxion can be observed in certain parameter regions.

Double scalar production at the ILC provides a clear signature for model identification.

Abstract

We propose a means to discriminate between the two basic variants of Little Higgs models, the Product Group and Simple Group models, at the next generation of colliders. It relies on a special coupling of light pseudoscalar particles present in Little Higgs models, the pseudoaxions, to the Z and the Higgs boson, which is present only in Simple Group models. We discuss the collider phenomenology of the pseudoaxion in the presence of such a coupling at the LHC, where resonant production and decay of either the Higgs or the pseudoaxion induced by that coupling can be observed for much of parameter space. The full allowed range of parameters, including regions where the observability is limited at the LHC, is covered by a future ILC, where double scalar production would be a golden channel to look for.