Cabibbo–Kobayashi–Maskawa Mixing in Superstring Derived Standard–like Models

We examine the problem of three generation quark flavor mixing in realistic, superstring derived standard–like models, constructed in the free fermionic formulation. We study the sources of family mixing in these models and discuss the necessary conditions to obtain a realistic Cabibbo–Kobayashi–Maskawa (CKM) mixing matrix. In a specific model, we estimate the mixing angles and discuss the weak CP violating phase. We argue that the superstring standard–like models can produce a realistic CKM mixing matrix. We discuss the possible textures of quark mass matrices that may be obtained in these models. ∗ e–mail address: [email protected]. Address after September 1 1993, School of Natural Sciences, Institute for Advanced Study, Olden Lane, Princeton NJ, 08540. † e–mail address: [email protected]