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arXiv · 2007.12695

CKM Substructure

Yuval Grossman·Joshua T. Ruderman
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Abstract

The CKM matrix is not generic. The Wolfenstein parametrization encodes structure by having one small parameter, $\lambda \approx 0.22$. We pose the question: is there substructure in the CKM matrix that goes beyond the single small parameter of the Wolfenstein parameterization? We find two relations that are approximately satisfied: $|V_{td}|^2 = |V_{cb}|^3$ and $|V_{ub}|^2 |V_{us}| = |V_{cb}|^4$. We discuss the statistical significance of these relations and find that they may indicate deeper structure in the CKM matrix. The current precision, however, cannot exclude an $\mathcal{O}(10 \%)$ accident.

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Yuval Grossman, Joshua T. Ruderman. 2020-07-24. CKM Substructure. https://doi.org/10.1007/jhep01(2021)143

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