Flavor in Supersymmetry with an Extended R-symmetry

Abstract

We propose a new solution to the supersymmetric flavor problem without flavor-blind mediation. Our proposal is to enforce a continuous or a suitably large discrete R-symmetry on weak scale supersymmetry, so that Majorana gaugino masses, trilinear A-terms, and the mu-term are forbidden. We find that replacing the MSSM with an R-symmetric supersymmetric model allows order one flavor-violating soft masses, even for squarks of order a few hundred GeV. The minimal R-symmetric supersymmetric model contains Dirac gaugino masses and R-symmetric Higgsino masses with no left-right mixing in the squark or slepton sector. Dirac gaugino masses of order a few TeV with vanishing A-terms solve most flavor problems, while the R-symmetric Higgs sector becomes important at large tan(beta). epsilon_K can be accommodated if CP is preserved in the SUSY breaking sector, or if there is a moderate flavor degeneracy, which can arise naturally. epsilon'/epsilon, as well as neutron and electron EDMs are easily within experimental bounds. The most striking phenomenological distinction of this model is the order one flavor violation in the squark and slepton sector, while the Dirac gaugino masses tend to be significantly heavier than the corresponding squark and slepton masses.