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A Precise Determination of the Pion-Nuclear Coupling Parameter from Weak Processes in ^3He

Nimai C. Mukhopadhyay·K. Junker
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Abstract

We utilize precise weak interaction experiments on atomic muon capture and beta decay in the A = 3 nuclei, and take into account the effects of nuclear "anomalous thresholds" to extract the pseudoscalar pi-^3He-^3H coupling parameter, G^{eff}(m_π^2) = 45.8+- 2.4. This is an order of magnitude improvement in precision over that from the use of pion-nuclear scattering data and dispersion relations.

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Nimai C. Mukhopadhyay, K. Junker. 1996-12-13. A Precise Determination of the Pion-Nuclear Coupling Parameter from Weak Processes in ^3He. https://doi.org/10.1103/physrevlett.77.5342

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