Abstract:
Precise measurements of the ft-values for superallowed nuclear β-decay yield results that support conservation of the weak vector current but violate the unitarity of the Cabibbo-Kobayashi-Maskawa matrix by more than two standard deviations. This apparent violation of the Standard Model has led to considerable theoretical and experimental activity largely focussed on reducing uncertainties in the small correction terms that account for charge-dependent nuclear effects. This activity is outlined and the prospects for future sharpening of the unitarity test are assessed.
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Received: 21 March 2002 / Accepted: 16 May 2002 / Published online: 31 October 2002
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Hardy, J., Towner, I. Superallowed 0+ → 0+ beta-decay and CKM unitarity . Eur Phys J A 15, 223–227 (2002). https://doi.org/10.1140/epja/i2001-10258-0
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DOI: https://doi.org/10.1140/epja/i2001-10258-0