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Pion-delta sigma-term

I. P. Cavalcante·M. R. Robilotta·J. Sa Borges·D. de O. Santos·G. R. S. Zarnauskas
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Abstract

We use a configuration space chiral model in order to evaluate nucleon and delta sigma-terms. Analytic expressions are consistent with chiral counting rules and give rise to expected non-analytic terms in the chiral limit. We obtain the results $σ_N=46$ MeV and $σ_Δ=32$ MeV, which are very close to values extracted from experiment and produced by other groups.

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I. P. Cavalcante, M. R. Robilotta, J. Sa Borges, D. de O. Santos, G. R. S. Zarnauskas. 2005-07-12. Pion-delta sigma-term. https://doi.org/10.1103/physrevc.72.065207

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