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arXiv · hep-ph/9512233

The Pion-Nucleon Sigma Term and the Goldberger-Treiman Discrepancy

James V. Steele·Hidenaga Yamagishi·Ismail Zahed
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Abstract

The pion-nucleon sigma term is shown to be equal to the Goldberger-Treiman discrepancy at tree level. Its value estimated this way is very sensitive to the pion-nucleon coupling constant g_{pi NN}. This relation, when combined with the pion-nucleon S-wave scattering lengths, yields a new determination of g_{pi NN} at tree level. The results of a one-loop analysis are also summarized determining an allowed range for the induced pseudoscalar coupling constant g_P.

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James V. Steele, Hidenaga Yamagishi, Ismail Zahed. 1995-12-04. The Pion-Nucleon Sigma Term and the Goldberger-Treiman Discrepancy. https://arxiv.org/abs/hep-ph/9512233

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