Goldilocks Supersymmetry: Simultaneous Solution to the Dark Matter and Flavor Problems of Supersymmetry

TL;DR

This paper proposes a novel supersymmetry model where neutralinos decay into gravitinos, simultaneously solving dark matter abundance issues and flavor violation constraints, with implications for high-scale gauge-mediation theories.

Contribution

It introduces a mechanism where neutralinos decay into gravitinos, addressing both dark matter density and flavor constraints in supersymmetry models.

Findings

Neutralinos decay into gravitinos, matching observed dark matter density.

The scenario fits naturally within high-scale gauge-mediation models.

It alleviates small scale structure problems in cosmology.

Abstract

Neutralino dark matter is well motivated, but also suffers from two shortcomings: it requires gravity-mediated supersymmetry breaking, which generically violates flavor constraints, and its thermal relic density \Omega is typically too large. We propose a simple solution to both problems: neutralinos freezeout with \Omega ~10-100, but then decay to ~1 GeV gravitinos, which are simultaneously light enough to satisfy flavor constraints and heavy enough to be all of dark matter. This scenario is naturally realized in high-scale gauge-mediation models, ameliorates small scale structure problems, and implies that ``cosmologically excluded'' models may, in fact, be cosmologically preferred.