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arXiv · hep-ph/0209226

The pionic beta decay in chiral perturbation theory

V. Cirigliano·M. Knecht·H. Neufeld·H. Pichl
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Abstract

Within the framework of chiral perturbation theory with virtual photons and leptons, we present an updated analysis of the pionic beta decay including all electromagnetic contributions of order e**2 p**2. We discuss the extraction of the Cabibbo-Kobayashi-Maskawa matrix element |Vud| from experimental data. The method employed here is consistent with the analogous treatment of the Kl3 decays and the determination of |Vus|.

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V. Cirigliano, M. Knecht, H. Neufeld, H. Pichl. 2002-09-19. The pionic beta decay in chiral perturbation theory. https://doi.org/10.1140/epjc%2Fs2002-01093-2

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