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Quenching of spin operators in the calculation of radiative corrections for nuclear beta decay

I. S. Towner
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Abstract

Calculations of the axial-vector component to the radiative correction for superallowed Fermi $0^+ \rightarrow 0^+$ nuclear beta decay are here modified with quenched rather than free-nucleon coupling constants for the axial-vector and electromagnetic interactions with nucleons. The result increases the deduced value of $V_{ud}$ but does not restore unitarity in the CKM matrix.

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I. S. Towner. 1994-05-31. Quenching of spin operators in the calculation of radiative corrections for nuclear beta decay. https://doi.org/10.1016/0370-2693(94)91000-6

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