The μ- term in Effective Supergravity Theories

Original · EN

The Higgs mixing term coefficient μeff is calculated in the scalar potential in supergravity theories with string origin, in a model independent approach. A general low energy effective expression is derived, where new contributions are included which depend on the modular weights q₁,₂ of the Higgs superfields, the moduli and derivative terms. We find that in a class of models obtained in the case of compactifications of the heterotic superstring, the derivative terms are identically zero. Further, the total μeff-term vanishes identically if the sum of the two modular weights q₁+q₂ is equal to two. Subleading μ- corrections, in the presence of intermediate gauge symmetries predicted in viable string scenarios, are also discussed.