Dark Matter Constraints and the Neutralino Sector of the scNMSSM

Elham Aldufeery,Maien Binjonaid

doi:10.3390/universe7020031

Abstract

The neutralino sector of the semi-constrained next-to-minimal supersymmetric standard model is explored under recent experimental constraints, with special attention to dark matter (DM) limits. The effects of the upper and lower bounds of dark matter relic density and recent direct detection constraints on spin-independent and -dependent cross-sections are thoroughly analyzed. Particularly, we show which regions of the parameter space are ruled out due to the different dark matter constraints and the corresponding model-specific parameters: λ,κ,Aλ, and Aκ. We analyze all annihilation and co-annihilation processes (with heavier neutralinos and charginos) that contribute to the dark matter relic density. The mass components of the dark matter candidate, the lightest neutralino χ˜10, are studied, and the decays of heavy neutralinos and charginos, especially χ˜20 and χ˜1+, into the lightest neutralino are examined. We impose semi-universal boundary conditions at the Grand Unified Theory scale, and require a moderate range of tanβ≲10. We find that the allowed parameter space is associated with a heavy mass spectrum in general and that the lightest neutralino is mostly Higgsino with a mass range that resides mostly between 1000 and 1500 GeV. However, smaller mass values can be achieved if the DM candidate is bino-like or singlino-like.

Highlights

Collider searchers rely on detecting missing energy events that could arise from decays into dark matter (DM) particles; indirect detection depends on observations of astronomical events, such as gamma ray lines; and direct detection searches rely on observing possible elastic scattering events between DM particles and atomic nuclei
Considering the above, we explored the parameter space of the next-to-minimal supersymmetric standard model (NMSSM) under the semi-constrained boundary conditions on the Grand Unified Theory (GUT) scale exploiting state-of-the-art tools incorporating the latest DM constraints, as a major motivation for SUSY models to provide gauge coupling unification
The paper is organized as follows: In Section 2, we provide a brief overview of the superpotential of the NMSSM and the neutralino mass matrix, and introduce the necessary parameters of the model

Summary

Introduction

Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations. Certain scenarios of DM in the semi-constrained NMSSM (scNMSSM), which is the model we are considering, were recently investigated in [36,54] Most of these works do not include the most recent constraints from DM searches, especially those from direct detection. Considering the above, we explored the parameter space of the NMSSM under the semi-constrained boundary conditions on the GUT scale exploiting state-of-the-art tools incorporating the latest DM constraints, as a major motivation for SUSY models to provide gauge coupling unification. We analyzed how relic density abundance constraints, as well as recent direct detection limits, affect the model, without a particular focus on specific regions, except for relatively moderate tan β .

The NMSSM and Its Neutralino Sector

The Parameter Space

Mapping DM Constraints into the Model’s Parameters

Properties of the Mass of the Neutralino DM

Contributions to Dark Matter Relic Density

Discussion and Conclusions