Moduli mediation without moduli-induced gravitino problem

TL;DR

This paper proposes a solution to the moduli-induced gravitino problem in supersymmetry models by introducing an extra light modulus field that dilutes gravitino abundance without causing additional supersymmetry breaking, applicable to various SUSY scales.

Contribution

The paper introduces a novel mechanism involving an extra light modulus field to mitigate the gravitino problem in mirage mediation frameworks, linking it to flux compactifications in string theory.

Findings

Successful dilution of gravitinos via extra modulus field.

Applicability to both low- and high-scale SUSY breaking.

Connection to flux compactification in string theory.

Abstract

We study the moduli-induced gravitino problem within the framework of the phenomenologically attractive mirage mediations. The huge amount of gravitino generated by the moduli decay can be successfully diluted by introducing an extra light modulus field which does not induce the supersymmetry breaking. Since the lifetime of extra modulus field becomes longer than usually considered modulus field, our proposed mechanism is applied to both the low- and high-scale supersymmetry breaking scenarios. We also point out that such an extra modulus field appears in the flux compactification of type II string theory.