A U(2)^3 flavour symmetry in Supersymmetry

TL;DR

This paper explores a U(2)^3 flavour symmetry in supersymmetry, explaining quark hierarchies, addressing collider constraints, and predicting specific flavour mixing patterns that could resolve CKM tensions and suggest new CP violation effects.

Contribution

It introduces a specific U(2)^3 flavour symmetry breaking pattern in supersymmetry, linking flavour observables to new physics signatures and collider phenomenology.

Findings

Correlation between K, B_d, B_s mixing amplitudes resolves CKM tensions.

Sbottom and gluino masses below about 1.5 TeV are favored.

Potential sizeable CP violation effects in B decays without flavour-blind phases.

Abstract

A U(2)^3 flavour symmetry acting on the first two generations of quarks partially explains the hierarchies of the yukawa couplings, and provides a natural embedding for Supersymmetry with heavier first two generations, where collider constraints are not in conflict with the requirement of naturalness and the SUSY CP problem is solved. Within this context a specific pattern of flavour symmetry breaking is considered. The K, B_d and B_s mixing amplitudes show a definite correlation that can resolve existing tensions in the CKM fit, pointing in this way to sbottom and gluino masses below about 1.5 TeV. Potentially sizeable contributions to both indirect and direct CP violation in B decays are allowed, even in the absence of flavour-blind phases. In case some effects are observed, the peculiar pattern in Delta(F) = 2 and Delta(B) = 1 observables may allow to distinguish between this and other models.