Radiative Corrections to Scalar Masses and Mixing in a Scale Invariant Two Higgs Doublet Model

TL;DR

This paper investigates the Higgs mass spectrum in a scale-invariant two-Higgs-doublet model, analyzing quantum corrections and experimental constraints to determine viable heavy Higgs masses and their degeneracies.

Contribution

It provides a detailed analysis of radiative corrections and experimental constraints in the SI-2HDM, identifying allowed parameter space and specific mass predictions for heavy Higgs bosons.

Findings

Heavy Higgs bosons near 400 GeV are favored.

Degeneracy between charged and one neutral Higgs is typical.

Third neutral Higgs is lighter than approximately 500 GeV.

Abstract

We study the Higgs-boson mass spectrum of a classical scale-invariant realization of the two-Higgs-doublet model (SI-2HDM). The classical scale symmetry of the theory is explicitly broken by quantum loop effects due to gauge interactions, Higgs self-couplings and top-quark Yukawa couplings. We determine the allowed parameter space compatible with perturbative unitarity and electroweak precision data. Taking into account the LEP and the recent LHC exclusion limits on a Standard-Model-like Higgs boson H_SM, we obtain rather strict constraints on the mass spectrum of the heavy Higgs sector of the SI-2HDM. In particular, if M_{H_SM} \sim 125 GeV, the SI-2HDM strongly favours scenarios, in which at least one of the non-standard neutral Higgs bosons has a mass close to 400 GeV and is generically degenerate with the charged Higgs boson, whilst the third neutral Higgs scalar is lighter than ~ 500 GeV.