Flavor physics within and beyond the Standard Model

TL;DR

This paper reviews recent theoretical advances in flavor physics, focusing on CKM unitarity, potential new physics signals in meson mixing, and supersymmetric contributions to flavor-changing processes and lepton flavor violation.

Contribution

It introduces new tan-beta-enhanced corrections to FCNC amplitudes, reevaluates the origin of flavor violation in MSSM, and explores constraints from mu -> e gamma on GUT-scale Yukawa interactions.

Findings

Potential enhancement of CP asymmetry in B_d -> phi K_S due to new corrections

Reassessment of soft SUSY-breaking terms as the source of flavor violation

Constraints on GUT-scale Yukawa interactions from lepton flavor violation experiments

Abstract

I review recent progress in theoretical calculations related to the CKM unitarity triangle. After briefly discussing hints for new physics in B_d-B_d-bar mixing and B_s-B_s-bar mixing I present three topics of MSSM flavor physics: First I discuss new tan-beta-enhanced radiative corrections to flavor-changing neutral current (FCNC) amplitudes which go beyond the familiar Higgs-mediated FCNC diagrams and may enhance the mixing-induced CP asymmetry in B_d -> phi K_S. The second topic is a reappraisal of the idea that flavor violation originates from the soft supersymmetry-breaking terms. Finally I discuss how mu -> e gamma can be used to constrain the flavor structure of the dimension-5 Yukawa interactions which appear in realistic grand unified theories.