High-scale validity of a two Higgs doublet scenario: metastability included

TL;DR

This paper explores the parameter space of a Type II Two-Higgs Doublet Model, identifying regions where the electroweak vacuum is metastable with a lifetime exceeding the universe's age, consistent with collider and precision data, up to the Planck scale.

Contribution

It provides a comprehensive analysis of metastability in a Two-Higgs Doublet Model, including constraints from collider data and high-scale perturbativity, extending the viability of the model.

Findings

Large parameter regions allow metastable vacua with long lifetimes.

Metastability regions complement absolute stability zones across top quark mass range.

Model remains consistent up to the Planck scale without contradictions.

Abstract

We make an attempt to identify regions in a Type II Two-Higgs Doublet Model, which correspond to a metastable electroweak vacuum with lifetime larger than the age of the universe. We analyse scenarios which retain perturbative unitarity up to Grand unification and Planck scales. Each point in the parameter space is restricted using Data from the Large Hadron Collider (LHC) as well as flavor and precision electroweak constraints. We find that substantial regions of the parameter space are thus identified as corresponding to metastability, which compliment the allowed regions for absolute stability, for top quark mass at the high as well as low end of its currently allowed range. Thus, a two-Higgs doublet scenario with the electroweak vacuum, either stable or metastable, can sail through all the way up to the Planck scale without facing any contradictions.