Minimal Composite Higgs Model with Light Bosons

TL;DR

This paper presents a minimal composite Higgs model featuring a light Higgs boson and a potentially light CP-odd scalar, with distinctive decay modes affecting Higgs search strategies and predictions of heavier scalar states.

Contribution

It introduces a minimal composite Higgs framework with specific light scalar predictions and explores their phenomenological implications, including decay channels and mass bounds.

Findings

Light Higgs boson just above LEP limit

Potentially very light CP-odd scalar with astrophysical bounds

Predicted heavier scalars in the TeV range

Abstract

We analyze a composite Higgs model with the minimal content that allows a light Standard-Model-like Higgs boson, potentially just above the current LEP limit. The Higgs boson is a bound state made up of the top quark and a heavy vector-like quark. The model predicts that only one other bound state may be lighter than the electroweak scale, namely a CP-odd neutral scalar. Several other composite scalars are expected to have masses in the TeV range. If the Higgs decay into a pair of CP-odd scalars is kinematically open, then this decay mode is dominant, with important implications for Higgs searches. The lower bound on the CP-odd scalar mass is loose, in some cases as low as $\sim$ 100 MeV, being set only by astrophysical constraints.