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تسجيل مستخدم جديدA_4 model for the quark mass matrices
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We propose a model for the quark masses and mixings based on an A_4 family symmetry. Three scalar SU(2) doublets form a triplet of A_4. The three left-handed-quark SU(2) doublets are also united in a triplet of A_4. The right-handed quarks are singlets of A_4. The A_4-symmetric scalar potential leads to a vacuum in which two of the three scalar SU(2) doublets have expectation values with equal moduli. Our model makes an excellent fit of the observed |V_ub/V_cb|. The symmetry CP is respected in the charged gauge interactions of the quarks.
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