Direct neutralino searches in the NMSSM with gravitino LSP in the degenerate scenario

TL;DR

This paper investigates a two-component dark matter model within the NMSSM where a nearly degenerate gravitino and neutralino allow for high reheating temperatures and evade BBN constraints, focusing on direct neutralino detection.

Contribution

It introduces a degenerate scenario in the NMSSM with a gravitino LSP and neutralino NLSP, highlighting the viability of singlino-like neutralinos for dark matter detection.

Findings

Degenerate gravitino and neutralino masses avoid BBN bounds.

High reheating temperatures compatible with thermal leptogenesis.

Surviving points feature singlino-like neutralinos.

Abstract

In the present work a two-component dark matter model is studied adopting the degenerate scenario in the R-parity conserving NMSSM. The gravitino LSP and the neutralino NLSP are extremely degenerate in mass, avoiding the BBN bounds and obtaining a high reheating temperature for thermal leptogenesis. In this model both gravitino (absolutely stable) and neutralino (quasi-stable) contribute to dark matter, and direct detection searches for neutralino are discussed. Points that survive all the constraints correspond to a singlino-like neutralino.