Saving the Higgs Portal for Singlet Scalar Dark Matter

TL;DR

This paper proposes a simple extension to the Higgs-portal singlet scalar dark matter model, which significantly enlarges the viable parameter space by adding a second scalar singlet, thus easing existing experimental constraints.

Contribution

Introducing a second scalar singlet to the Higgs-portal model to open new viable regions in dark matter parameter space.

Findings

Extended model broadens allowed parameter space

Reduces constraints from direct and indirect detection

Potentially compatible with current collider limits

Abstract

The Higgs-portal model with a singlet scalar Dark Matter particle is one of the simplest extensions to the Standard Model that can reproduce the relic density. Unfortunately this model is strongly constrained by direct and indirect DM detection, as well as by collider physics. Most of the parameter space is already ruled-out and the rest will be explored in the next future. We show that a simple extension of the DM sector with a second scalar singlet enables a substantial opening of the allowed window in the parameter space.