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Simple Approach to Renormalize the Cabibbo-Kobayashi-Maskawa Matrix

Bernd A. Kniehl·Alberto Sirlin
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Abstract

We present an on-shell scheme to renormalize the Cabibbo-Kobayashi-Maskawa (CKM) matrix. It is based on a novel procedure to separate the external-leg mixing corrections into gauge-independent self-mass and gauge-dependent wave-function renormalization contributions, and to implement the on-shell renormalization of the former with non-diagonal mass counterterm matrices. Diagonalization of the complete mass matrix leads to an explicit CKM counterterm matrix, which automatically satisfies all the following important properties: it is gauge independent, preserves unitarity, and leads to renormalized amplitudes that are non-singular in the limit in which any two fermions become mass degenerate.

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Bernd A. Kniehl, Alberto Sirlin. 2006-10-20. Simple Approach to Renormalize the Cabibbo-Kobayashi-Maskawa Matrix. https://doi.org/10.1103/physrevlett.97.221801

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