Higgs-mediated electric dipole moments in the MSSM: an application to baryogenesis and Higgs searches

Abstract

We perform a comprehensive study of the dominant two- and higher-loop contributions to the 205Tl, neutron and muon electric dipole moments induced by Higgs bosons, third-generation quarks and squarks, charginos and gluinos in the Minimal Supersymmetric Standard Model (MSSM). We find that strong correlations exist among the contributing CP-violating operators, for large stop, gluino and chargino phases, and for a wide range of values of tan β and charged Higgs-boson masses, giving rise to large suppressions of the 205Tl and neutron electric dipole moments below their present experimental limits. Based on this observation, we discuss the constraints that the non-observation of electric dipole moments imposes on the radiatively-generated CP-violating Higgs sector and on the mechanism of electroweak baryogenesis in the MSSM. We improve previously suggested benchmark scenarios of maximal CP violation for analyzing direct searches of CP-violating MSSM Higgs bosons at high-energy colliders, and stress the important complementary rôle that a possible high-sensitivity measurement of the muon electric dipole moment to the level of 10 −24 e cm can play in such analyses.