Composite Higgs Models with a Hidden Sector

TL;DR

This paper explores composite Higgs models with a hidden sector, predicting additional particles and signatures that are challenging to detect at current colliders but could be observed with future facilities.

Contribution

It introduces a framework where a hidden gauge sector influences the Higgs phenomenology, providing calculable scalar potentials and new pseudo-Nambu Goldstone bosons.

Findings

Additional pseudo-Nambu Goldstone bosons with electroweak-scale masses.

Collider signatures are generally difficult to detect at the LHC.

Future colliders or detectors could reveal hidden sector effects.

Abstract

We discuss the phenomenology of composite Higgs models that naturally produce a Standard Model-like Higgs boson with a mass of $126$ GeV. The effective theory below the compositeness scale is weakly coupled in these models, and the goldstone sector acts as a portal between the third generation of quarks and a hidden gauge sector. The addition of hidden-sector fermions gives rise to a calculable effective scalar potential with a naturally light scalar resonance. The generic prediction of these theories is the existence of additional pseudo-Nambu Goldstone bosons with electroweak-scale cross sections and masses. In this paper we analyze the collider signatures for some simple concrete realizations of this framework. We find that despite the existence of additional weakly and strongly coupled particles that are kinematically within reach of current experiments, the generic signatures are difficult to resolve at the LHC, and could remain well-hidden in the absence of an $e^+ e^-$ Higgs factory such as the CEPC or a surface detector such as MATHUSLA.