General Minimal Flavor Violation

TL;DR

This paper explores the minimal flavor violation framework, analyzing linear and nonlinear limits, and finds significant effects in the up-type quark sector, including CP violation and flavor violation, with implications for B and D meson systems.

Contribution

It introduces a model-independent analysis of MFV, employing non-linear sigma-model techniques to resum Yukawa couplings and explores the implications for CP violation and flavor processes.

Findings

Flavor diagonal CPV sources can induce O(1) CPV in third generation processes.

Residual U(2) symmetry bounds CPV in B_d and B_s mixing.

Large enhancements in CPV and flavor violation in the up-type quark sector.

Abstract

A model independent study of the minimal flavor violation (MFV) framework is presented, where the only sources of flavor breaking at low energy are the up and down Yukawa matrices. Two limits are identified for the Yukawa coupling expansion: linear MFV, where it is truncated at the leading terms, and nonlinear MFV, where such a truncation is not possible due to large third generation Yukawa couplings. These are then resummed to all orders using non-linear sigma-model techniques familiar from models of collective breaking. Generically, flavor diagonal CP violating (CPV) sources in the UV can induce O(1) CPV in processes involving third generation quarks. Due to a residual U(2) symmetry, the extra CPV in B_d-\bar B_d mixing is bounded by CPV in B_s-\bar B_s mixing. If operators with right-handed light quarks are subdominant, the extra CPV is equal in the two systems, and is negligible in processes involving only the first two generations. We find large enhancements in the up type sector, both in CPV in D-\bar D mixing and in top flavor violation.