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arXiv · 2307.13073

Unitarity Relations in the Presence of Vector-Like Quarks

Francisco Albergaria·Gustavo C. Branco
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Abstract

We study, in a systematic way, the $V_{\text{CKM}}$ unitarity relations which arise in extensions of the three generations Standard Model (3gSM) involving the addition of vector-like quarks (VLQ). In particular, we emphasize the effect of the presence of VLQ on $V_{\text{CKM}}$ moduli differences, as well on the size of the imaginary parts of rephasing invariant $V_{\text{CKM}}$ quartets. We consider the special case where an up-type VLQ is used to attempt at solving the unitarity problem in the first line of $V_{\text{CKM}}$.

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Francisco Albergaria, Gustavo C. Branco. 2023-07-24. Unitarity Relations in the Presence of Vector-Like Quarks. https://arxiv.org/abs/2307.13073

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