Current status and prospects of light bino-higgsino dark matter in natural SUSY

TL;DR

This paper examines the viability of light bino-higgsino dark matter within natural supersymmetry, considering recent experimental constraints and projecting future collider searches.

Contribution

It provides a systematic analysis of the light bino-higgsino DM scenario under natural SUSY, incorporating latest experimental bounds and future collider prospects.

Findings

Part of the parameter space remains viable after current constraints.

The neutralino relic density is below the observed dark matter density.

Future 14 TeV LHC runs will probe the remaining parameter space.

Abstract

Given recent advancements in dark matter (DM) search experiments, particularly the latest LUX-ZEPLIN (LZ) direct detection (DD) results, we systematically investigate the light bino-higgsino DM scenario within the natural supersymmetric framework. Requiring the electroweak fine-tuning parameter $\Delta_{\text{EW}} < 30$ fixes the higgsino mass parameter in the range $|\mu| \in [100, 350]$ GeV, while we extend the bino mass to $M_1 \in [10, 350]$ GeV. Incorporating constraints from Higgs physics, rare $B$ decays, LEP limits, and DD experiments, we find that part of the parameter space remains viable. However, the relic density of neutralino DM necessarily lies below the observed Planck value, contributing at most $\sim 2\%$ of the total DM abundance. Some of the surviving parameter space is already excluded by current 13 TeV LHC searches, while the future 14 TeV HL-LHC with 3000 fb$^{-1}$ luminosity will probe the remaining region.