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arXiv · hep-ph/9604214

Violations of universality in a vectorlike extension of the standard model

István Montvay
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Abstract

Violations of universality of couplings in a vectorlike extension of the standard model with three heavy mirror fermion families are considered. The recently observed discrepancies between experiments and the standard model in the hadronic branching fractions $R_b$ and $R_c$ of the Z-boson are explained by the mixing of fermions with their mirror fermion partners.

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István Montvay. 1996-04-02. Violations of universality in a vectorlike extension of the standard model. https://doi.org/10.1016/0370-2693(96)00605-3

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