Flavor Changing Processes in Supersymmetric Models with Hybrid Gauge- and Gravity-Mediation

TL;DR

This paper explores supersymmetric models combining gauge and gravity mediation, analyzing their flavor-changing effects and constraints from meson mixing, highlighting potential deviations from the Standard Model predictions.

Contribution

It introduces a class of hybrid gauge-gravity mediated supersymmetric models with flavor constraints and quantifies their impact on meson mixing and flavor violation processes.

Findings

Neutral B system mixing deviations up to 10% for large tan beta

D system mixing deviations up to a few percent, possibly one in special cases

Identification of relevant ΔB=1 flavor violation processes

Abstract

We consider supersymmetric models where gauge mediation provides the dominant contributions to the soft supersymmetry breaking terms while gravity mediation provides sub-dominant yet non-negligible contributions. We further assume that the gravity-mediated contributions are subject to selection rules that follow from a Froggatt-Nielsen symmetry. This class of models constitutes an example of viable and natural non-minimally flavor violating models. The constraints from mixing in the neutral K system imply that the modifications to the Standard Model predictions for mixing in the neutral B_d and B_s systems are generically at most at the percent level, but can be of order ten percent for large $\tan \beta$. The modifications for the neutral D system mixing are generically at most of order a few percent, but in a special subclass of models they can be of order one. We point out $\Delta B=1$ processes relevant for flavor violation in hybrid mediation.