Di-boson signatures as Standard Candles for Partial Compositeness

TL;DR

This paper investigates scalar resonances in composite Higgs models, demonstrating their potential as early indicators of new physics through di-boson signatures, and provides a framework for constraining such models.

Contribution

It introduces a generic framework to analyze scalar resonances in composite Higgs models and assesses their phenomenology against experimental bounds.

Findings

Scalar signatures impose strong bounds on the compositeness scale.

Light scalars could be detectable as early signs of new physics.

The framework applies to models with pseudo-scalar singlets or octets.

Abstract

Composite Higgs Models are often constructed including fermionic top partners with a mass around the TeV scale, with the top partners playing the role of stabilizing the Higgs potential and enforcing partial compositeness for the top quark. A class of models of this kind can be formulated in terms of fermionic strongly coupled gauge theories. A common feature they all share is the presence of specific additional scalar resonances, namely two neutral singlets and a colored octet, described by a simple effective Lagrangian. We study the phenomenology of these scalars, both in a model independent and model dependent way, including the bounds from all the available searches in the relevant channels with di-boson and di-top final states. We develop a generic framework which can be used to constrain any model containing pseudo-scalar singlets or octets. Using it, we find that such signatures provide strong bounds on the compositeness scale complementary to the traditional EWPT and Higgs couplings deviations. In many cases a relatively light scalar can be on the verge of discovery as a first sign of new physics.