Induced pseudoscalar coupling of the proton weak interaction

Tim Gorringe; Harold W. Fearing

doi:10.1103/revmodphys.76.31

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Induced pseudoscalar coupling of the proton weak interaction

Tim Gorringe·Harold W. Fearing

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Abstract

The induced pseudoscalar coupling $g_p$ is the least well known of the weak coupling constants of the proton's charged--current interaction. Its size is dictated by chiral symmetry arguments, and its measurement represents an important test of quantum chromodynamics at low energies. During the past decade a large body of new data relevant to the coupling $g_p$ has been accumulated. This data includes measurements of radiative and non radiative muon capture on targets ranging from hydrogen and few--nucleon systems to complex nuclei. Herein the authors review the theoretical underpinnings of $g_p$, the experimental studies of $g_p$, and the procedures and uncertainties in extracting the coupling from data. Current puzzles are highlighted and future opportunities are discussed.

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Tim Gorringe, Harold W. Fearing. 2002-06-18. Induced pseudoscalar coupling of the proton weak interaction. https://doi.org/10.1103/revmodphys.76.31

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