Gauge Mediation beyond Minimal Flavor Violation

TL;DR

This paper explores a modified gauge mediation model where messenger fields couple to matter, leading to a predictable SUSY spectrum that can explain a 126 GeV Higgs and suppress flavor violations, aligning with recent CP violation observations.

Contribution

It introduces a minimal extension of gauge mediation with direct messenger-matter couplings linked to flavor hierarchies, resulting in a calculable spectrum and suppressed flavor violations.

Findings

Achieves a 126 GeV Higgs with a light SUSY spectrum.

Suppresses flavor-violating effects in Delta F=2 processes.

Provides a framework to explain CP violation in D-meson decays.

Abstract

We study a minimal modification of Gauge Mediation in which the messenger sector couples directly to the MSSM matter fields. These couplings are controlled by the same dynamics that explain the flavor hierarchies, and therefore are parametrically as small as the Yukawas. This setup gives rise to an interesting SUSY spectrum that is calculable in terms of a single new parameter. Due to large A-terms, the model can easily accommodate a 126 GeV Higgs with a relatively light SUSY spectrum. The flavor structure depends on the particular underlying flavor model, but flavor-violating effects arise dominantly in the up-sector and are strongly suppressed in Delta F =2 observables. This strong suppression is reminiscent of what happens in the case of wave function renormalization or Partial Compositeness, despite the underlying flavor model can be a simple U(1) flavor model (which in the context of Gravity Mediation suffers from strong Delta F =2 constraints). This structure allows to account for the recent observation of direct CP violation in D-meson decays.