Two Component Higgs-Portal Dark Matter

TL;DR

This paper develops a two-component Higgs-portal dark matter model addressing fine-tuning, vacuum stability, and unitarity issues, with constraints from relic density and detection experiments, and shows potential for stability up to the Planck scale.

Contribution

It introduces a novel two-component dark matter framework that relaxes fine-tuning and stabilizes the Higgs potential up to high energy scales.

Findings

Fine-tuning problem is relaxed compared to the Standard Model.

Vacuum stability is improved with two dark matter singlets.

Parameter space exists where Higgs quartic coupling remains positive up to Planck scale.

Abstract

In this paper, we construct two component dark matter model and revisit fine-tuning, unitarity and vacuum stability problem in this framework. Through Higgs-portal interactions, the additional scalar and vector singlet field can interact with the SM particles. The parameter space of the model are severely constraint by observed relic density and direct detection experiments. We found that, unlike the SM, the fine-tuning problem is relaxed due to the modified Veltman condition. The vacuum stability problem is addressed, the additional contributions from two DM singlets to the $\beta$ function make the Higgs quartic coupling $\lambda(\mu)$ be positive up to Planck scale in some parameter space.