Gravitational rescue of minimal gauge mediation

TL;DR

This paper explores a hybrid supersymmetry breaking model combining gauge and gravity mediation, using a two-spurion hidden sector in a warped Randall-Sundrum framework to achieve desirable phenomenological features.

Contribution

It introduces a complete two-spurion hidden sector model with warped geometry to balance gravity and gauge mediation effects in supersymmetry breaking.

Findings

Gravity contributions can be tuned to modify the soft SUSY breaking sector.

A hierarchical two-spurion hidden sector enables controlled gravitational effects.

Derived simple RG equations for mixed SUSY breaking scenarios.

Abstract

Gravity mediation supersymmetry breaking become comparable to gauge mediated supersymmetry breaking contributions when messenger masses are close to the GUT scale. By suitably tuning the gravity contributions one can then modify the soft supersymmetry breaking sector to generate a large stop mixing parameter and a light higgs mass of 125 GeV. In this kind of hybrid models, however the nice features of gauge mediation like flavour conservation etc, are lost. To preserve the nice features, gravitational contributions should become important for lighter messenger masses and should be important only for certain fields. This is possible when the hidden sector contains multiple (at least two) spurions with hierarchical vaccum expectation values. In this case, the gravitational contribtutions can be organised to be `just right'. We present a complete model with two spurion hidden sector where the gravitational contribution is from a warped flavour model in a Randall-Sundrum setting. Along the way, we present simple expressions to handle renormalisation group equations when supersymmetry is broken by two different sectors at two different scales.