Large CP Violation in B_s Meson Mixing with EDM constraint in Supersymmetry

TL;DR

This paper explores the potential for large CP violation in B_s meson mixing within supersymmetry, considering electric dipole moment constraints and the effects of superparticle decoupling.

Contribution

It demonstrates that large CP violation is achievable in supersymmetry when superparticles are decoupled, overcoming EDM constraints that hinder such effects.

Findings

Large CP violation can be realized with superparticle decoupling.

Electric dipole moment constraints limit CP violation in gluino-dominated scenarios.

Branching ratio of B_s -> mu^+ mu^- can be significantly increased.

Abstract

Motivated by the recent measurement of the like-sign dimuon charge asymmetry, we investigate anomalous CP violation in the B_s- bar{B}_s mixing within the supersymmetry. We show that when gluino diagrams dominate supersymmetry contributions, it is very difficult to realize a large B_s- bar{B}_s mixing phase under the constraint from electric dipole moments barring cancellations. This constraint can be ameliorated by supposing superparticles decoupled. In this limit, we find that it is possible to achieve the large CP asymmetry, and the branching ratio of B_s -> mu^+ mu^- tends to become sizable.