Flavor Symmetry Based MSSM (sMSSM): Theoretical Models and Phenomenological Analysis

TL;DR

This paper introduces a class of supersymmetric models called sMSSM, where flavor symmetries dictate the soft SUSY breaking terms, addressing flavor violation, CP violation, and phenomenological constraints.

Contribution

The paper develops minimal sMSSM models with non-Abelian flavor symmetries, providing explicit constructions and solutions to D-term and CP problems, and analyzes their phenomenology.

Findings

Models suppress SUSY flavor violation effectively.

Solutions to D-term and CP problems are demonstrated.

Parameter space compatible with LHC, B physics, and dark matter constraints.

Abstract

We present a class of supersymmetric models in which symmetry considerations alone dictate the form of the soft SUSY breaking Lagrangian. We develop a class of minimal models, denoted as sMSSM -- for flavor symmetry-based minimal supersymmetric standard model, which respect a grand unified symmetry such as SO(10) and a non-Abelian flavor symmetry H which suppresses SUSY-induced flavor violation. Explicit examples are constructed with the flavor symmetry being gauged SU(2)_H and SO(3)_H with the three families transforming as 2 + 1 and 3 representations respectively. A simple solution is found in the case of SU(2)_H for suppressing the flavor violating D--terms based on an exchange symmetry. Explicit models based on SO(3)_H without the D--term problem are developed. In addition, models based on discrete non-Abelian flavor groups are presented which are automatically free from D--term issues. The permutation group S_3 with a 2 + 1 family assignment, as well as the tetrahedral group A_4 with a 3 assignment are studied. In all cases, a simple solution to the SUSY CP problem is found, based on spontaneous CP violation leading to a complex quark mixing matrix. We develop the phenomenology of the resulting sMSSM, which is controlled by seven soft SUSY breaking parameters for both the 2 + 1 assignment and the 3 assignment of fermion families. These models are special cases of the phenomenological MSSM (pMSSM), but with symmetry restrictions. We discuss the parameter space of sMSSM compatible with LHC searches, B physics constraints and dark matter relic abundance. Fine-tuning in these models is relatively mild, since all SUSY particles can have masses below about 3 TeV.