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The KM phase in semi-realistic heterotic orbifold models

Joel Giedt
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Abstract

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.

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Joel Giedt. 2001-12-17. The KM phase in semi-realistic heterotic orbifold models. https://doi.org/10.1016/s0550-3213(00)00620-9

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