Exploring CP Violation in the MSSM

TL;DR

This paper investigates the potential for observing CP violation in the MSSM through various observables, using computational methods and considering experimental constraints, revealing promising signals for future experiments.

Contribution

It introduces a comprehensive analysis of CP violation in the MSSM with six CP-violating parameters, employing a geometric approach and exploring multiple MSSM scenarios.

Findings

CP asymmetry A_CP in b -> s gamma can reach 3%.

Contributions to B_s meson mixing are below current limits but could be constrained with reduced uncertainties.

Large CP violation potential in Higgs couplings to tau and top quarks for future collider detection.

Abstract

We explore the prospects for observing CP violation in the minimal supersymmetric extension of the Standard Model (MSSM) with six CP-violating parameters, three gaugino mass phases and three phases in trilinear soft supersymmetry-breaking parameters, using the CPsuperH code combined with a geometric approach to maximize CP-violating observables subject to the experimental upper bounds on electric dipole moments. We also implement CP-conserving constraints from Higgs physics, flavour physics and the upper limits on the cosmological dark matter density and spin-independent scattering. We study possible values of observables within the constrained MSSM (CMSSM), the non-universal Higgs model (NUHM), the CPX scenario and a variant of the phenomenological MSSM (pMSSM). We find values of the CP-violating asymmetry A_CP in b -> s gamma decay that may be as large as 3%, so future measurements of A_CP may provide independent information about CP violation in the MSSM. We find that CP-violating MSSM contributions to the B_s meson mass mixing term Delta M_Bs are in general below the present upper limit, which is dominated by theoretical uncertainties. If these could be reduced, Delta M_Bs could also provide an interesting and complementary constraint on the six CP-violating MSSM phases, enabling them all to be determined experimentally, in principle. We also find that CP violation in the h_{2,3} tau+ tau- and h_{2,3} tbar t couplings can be quite large, and so may offer interesting prospects for future pp, e+ e-, mu+ mu- and gamma gamma colliders.