Two Higgs Doublets from Fermion Condensation

TL;DR

This paper explores a two-Higgs doublet model arising from fermion condensation in strongly coupled sectors, predicting a lighter scalar spectrum with a pseudo-scalar as the lightest state, impacting phenomenology.

Contribution

It introduces a two-Higgs doublet model from fermion condensation, estimating the scalar spectrum and highlighting a lighter spectrum with a pseudo-scalar as the lightest particle.

Findings

Scalar spectrum lighter than single fermion condensation models

Lightest state is a pseudo-scalar with 10-120 GeV mass range

Distinct phenomenological signatures due to the spectrum

Abstract

We consider the most generic situation in models where the electroweak symmetry is broken by the condensation of a strongly coupled fermion sector, such as for instance a fourth generation. We study the scalar content resulting from the condensation of both the up and the down type fermions, corresponding to a two-Higgs doublet model. We estimate the scalar spectrum using the Nambu--Jona-Lasinio model, improved by the renormalization group. We show that the scalar spectrum is generically lighter than for the case with only one right-handed fermion condensing and that due to a remnant Peccei-Quinn symmetry the lightest state is the pseudo-scalar, with masses ranging typically from 10 GeV to 120 GeV. We discuss the phenomenological consequences of this distinct spectrum.