Higgsino Asymmetry and Direct-Detection Constraints of Light Dark Matter in the NMSSM with Non-Universal Higgs Masses

TL;DR

This paper investigates how higgsino asymmetry influences spin-dependent cross sections in light dark matter within the NMSSM with non-universal Higgs masses, revealing correlations and potential detection prospects.

Contribution

It establishes the proportionality between higgsino asymmetry and spin-dependent cross section and analyzes relic density and detection implications for different dark matter compositions.

Findings

Spin-dependent cross section is proportional to higgsino asymmetry.

Highly singlino-dominated dark matter has small higgsino asymmetry and cross section.

Future LZ experiments can detect certain light dark matter scenarios.

Abstract

In this work, we study the direct-detection constraints of light dark matter in the next-to minimal supersymmetric standard model (NMSSM) with non-universal Higgs masses (NUHM), especially the correlation between higgsino asymmetry and spin-dependent cross section. Finally, we get the following conclusions: (i) The spin-dependent cross section is proportional to the square of higgsino asymmetry in dark matter $\tilde{\chi}^0_1$ in the NMSSM-NUHM. (ii) For highly singlino-dominated dark matter $\tilde{\chi}^0_1$, the relic density can be sufficient, but the higgsino asymmetry and spin-dependent cross section is always small. (iii) With a sizeable higgsino component in the light dark matter, the higgsino asymmetry and spin-dependent cross section can be sizeable, but dark matter relic density is always small, thus it can escape the direct detections. (iv) Light dark matter in the $h_2$- and $Z$-funnel annihilation channels with sufficient relic density can be covered by future LUX-ZEPLIN (LZ) 7-ton in spin-dependent detections.