Cp Violation in Supersymmetric Theories

Abstract

We review the present status of CP violating problem in supersymmetric extensions of the standard model. We analyze the constraints imposed by the experimental limits of the electron, neutron, and mercury electric dipole moments on the supersymmetric CP phases and show that only the scenarios with flavour-off-diagonal CP violation remain attractive. These scenarios require hermitian Yukawa matrices which naturally arise in models with left-right symmetry or a SU (3) flavour symmetry. In this case, ε K and ε ′ /ε can be saturated by a small non-universality of the soft scalar masses through the gluino and chargino contributions respectively. The model also predicts a strong correlation between A CP (b → sγ) and the neutron electric dipole moment. In this framework, the standard model gives a the leading contribution to the CP asymmetry in B → ψK S decay, while the dominant chargino contribution to this asymmetry is < 0.2. Thus, no constraint is set on the non-universality of this model by the recent BaBar and Belle measurements.

Strong CP violation and the neutron electric dipole form factor

“…The leading contribution to the EDFF comes from the linear term of the expansion in Eq. (18). Neglecting higher order terms, we adopt for our analysis the CP-violating interaction in the form:…”

“…In particular, supersymmetric extensions of the SM offer additional mechanisms for CP-violation [14]- [19] originating from complex phases in the soft SUSY breaking terms and superpotential parameters (for a review see Ref. [18]). …”

Quantum Dynamics in Atomic-Fountain Experiments for Measuring the Electric Dipole Moment of the Electron with Improved Sensitivity

“…The present limit on the electron EDM already presses supersymmetry (SUSY), especially when that limit is combined with those on the neutron EDM and those on the EDMs of diamagnetic atoms. Present limits on the electron EDM [14,15] are lower by a factor of 100 than EDMs predicted by some SUSY models [16][17][18][19][20][21] with super-partner masses of 100 GeV and CP violating phases of order unity. Therefore, these SUSY models could be excluded.…”

Leptogenesis in supersymmetry with one L violating coupling

“…Such heavy masses are consistent [60] with the kind of Higgs mass observed at LHC. Besides, because of sfermion masses in few TeV scale or more, it is difficult to constrain Majorana phases [61,62] even after recent improvement on the experimental bound of electric dipole moment of particularly electron [63]. So the phase φ = π/4 as considered in our numerical analysis, is easily allowed.…”