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arXiv · 1704.06993

The discrete charm of flavour and CP violation

G. C. Branco·M. N. Rebelo
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Abstract

We point out that in the Standard Model (SM) there is no explanation why $|V_{23}|^2 + |V_{13}|^2$ is of order $10^{-3}$. A framework is described for explaining this small mixing, involving the introduction of vector-like quarks. A symmetry is introduced so that at a first stage $V_{CKM} = 1\>\!\!\!\mathrm{I}$ and only the third generation of quarks acquires a mass. It is shown that when interactions of vector-like quarks are taken into account a realistic quark mass spectrum is generated together with a correct $V_{CKM}$ matrix.

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G. C. Branco, M. N. Rebelo. 2017-04-23. The discrete charm of flavour and CP violation. https://doi.org/10.1088/1742-6596/873/1/012011

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