Light dark matter in a minimal extension with two additional real singlets

TL;DR

This paper explores a minimal extension of the Standard Model with two real singlets that can accommodate light dark matter, matching observed relic density, and predicts detectable changes in Higgs decay signatures at CERN.

Contribution

It introduces a simple model with two additional singlets that explains light dark matter and predicts enhanced invisible Higgs decay rates observable at colliders.

Findings

The model can produce the correct relic dark matter density.

It does not conflict with big-bang nucleosynthesis or CMB observations.

It predicts increased invisible Higgs decay rates detectable at CERN.

Abstract

The direct searches for heavy scalar dark matter with a mass of order 100 GeV are much more sensitive than for light dark matter of order 1 GeV. The question arises whether dark matter could be light and has escaped detection so far. We study a simple extension of the Standard Model with two additional real singlets. We show that this simple extension may provide the observed relic dark matter density, does neither disturb big-bang nucleosynthesis nor the cosmic microwave background radiation observations and fulfills the conditions of clumping behavior for different sizes of galaxies. The potential of one Standard Model-like Higgs-boson doublet and the two singlets gives rise to a changed Higgs phenomenology, in particular, an enhanced invisible Higgs-boson decay rate is expected, detectable by missing transversal momentum searches at the ATLAS and CMS experiments at CERN.