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arXiv · 2210.14248

CP-odd and CP-even Weak-Basis Invariants in the Presence of Vector-Like Quarks

Francisco Albergaria·G. C. Branco·José Filipe Bastos·J. I. Silva-Marcos
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Abstract

We propose a minimal set of weak-basis invariants in an extension of the SM where one up-type isosinglet vector-like quark is introduced, which allows us to obtain all the physical content of the CKM matrix. We present CP-odd invariants of lower order in mass than the one in the SM, which may have important consequences for Baryogenesis. We study the extreme chiral limit, where the two lightest generations have vanishing mass, showing that in this extension, contrary to the SM, CP violation can be observed in collisions much above the electroweak scale.

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Francisco Albergaria, G. C. Branco, José Filipe Bastos, J. I. Silva-Marcos. 2022-10-25. CP-odd and CP-even Weak-Basis Invariants in the Presence of Vector-Like Quarks. https://doi.org/10.1088/1361-6471%2Facc349

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