In string-inspired semi-realistic heterotic orbifolds models with an anomalous U(1) X, a nonzero Kobayashi-Masakawa (KM) phase is shown to arise generically from the expectation values of complex scalar fields, which appear in nonrenormalizable quark mass couplings. Modular covariant nonrenormalizable superpotential couplings are constructed. A toy Z 3 orbifold model is analyzed in some detail. Modular symmetries and orbifold selection rules are taken into account and do not lead to a cancellation of the KM phase. We also discuss attempts to obtain the KM phase solely from renormalizable interactions.
Nuclear Physics B
- Pub Date:
- February 2001
- High Energy Physics - Phenomenology;
- High Energy Physics - Theory;
- Mathematical Physics
- Error in Section 2, "Counterexamples," corrected