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Neutron beta-decay and the quark-mixing CKM-matrix

Hartmut Abele
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Abstract

Neutrons study a number of hot topics from the field of particle physics and cosmology: Recent measurements of various mixed American-British-French-German-Hungarian-Japan-Russian groups of researchers determine the strength of the weak interaction of the neutron, which gives us unique information on quark-mixing and the question of unitarity. Much to our surprise, with neutron-decay we find a deviation Delta = 0.0083(28) from the unitarity condition, an effect that cannot be explained by the current Standard Model of particle physics.

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Hartmut Abele. 2002-08-29. Neutron beta-decay and the quark-mixing CKM-matrix. https://arxiv.org/abs/hep-ex/0208048

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