Light dark matter in the singlet-extended MSSM

TL;DR

This paper explores a singlet-extended MSSM model where light singlino dark matter particles can explain certain experimental signals and remain consistent with current constraints, offering a viable dark matter candidate.

Contribution

It introduces a model with a light scalar mediator and singlino LSPs that can account for experimental signals and cosmological relic abundance.

Findings

Singlino masses of a few GeV can explain CRESST, CoGeNT, and DAMA signals.

The scalar mediator can be consistent with experimental constraints.

Annihilation into scalars yields the correct relic density.

Abstract

We discuss the possibility of light dark matter in a general singlet extension of the MSSM. Singlino LSPs with masses of a few GeV can explain the signals reported by the CRESST, CoGeNT and possibly also DAMA experiments. The interactions between singlinos and nuclei are mediated by a scalar whose properties coincide with those of the SM Higgs up to two crucial differences: the scalar has a mass of a few GeV and its interaction strengths are suppressed by a universal factor. We show that such a scalar can be consistent with current experimental constraints, and that annihilation of singlinos into such scalars in the early universe can naturally lead to a relic abundance consistent with the observed density of cold dark matter.