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Pion nucleon coupling constant, Goldberger-Treiman discrepancy and $πN$ $σ$ term

Miroslav Nagy·Michael D. Scadron·Gerald E. Hite
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Abstract

We start by studying the Goldberger-Treiman discrepancy (GTd) $Δ= (2.259\pm 0.591)%$. Then we look at the $πN$ $σ$ term, with the dimensionless ratio $σ_N/2m_N=3.35%$. Finally we return to predicting (via the quark model) the $πN$ coupling constant, with GTd $Δ\to 0$ as $m_q\to m_N/3$.

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Miroslav Nagy, Michael D. Scadron, Gerald E. Hite. 2004-09-07. Pion nucleon coupling constant, Goldberger-Treiman discrepancy and $πN$ $σ$ term. https://arxiv.org/abs/hep-ph/0406009

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