On Gaugino Contributions to Soft Leptogenesis

Abstract

We study the contributions to CP violation in right-handed sneutrino decays induced by soft supersymmetry-breaking gaugino masses including flavour effects and paying special attention to the role of thermal corrections. Using a field-theoretical as well as a quantum mechanical approach we compute the CP asymmetries and we conclude that for all the soft-supersymmetry breaking sources of CP violation considered, an exact cancellation between the asymmetries produced in the fermionic and bosonic channels occurs at T=0 up to second order in soft supersymmetry-breaking parameters. Once thermal effects are included the new sources of CP violation induced by supersymmetry-breaking gaugino masses can be sizeable and they can produce the observed baryon asymmetry for conventional values of the B parameter.

Comments: 20 pages, 4 figures