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Comparison of the extended linear sigma model and chiral perturbation theory

W. P. Alvarez·K. Kubodera·F. Myhrer
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Abstract

The pion-nucleon scattering amplitudes are calculated in tree approximation with the use of the extended linear sigma model (ELSM) as well as heavy baryon chiral perturbation theory (HB$χ$PT), and the non-relativistic forms of the ELSM results are compared with those of HB$χ$PT. We find that the amplitudes obtained in ELSM do not agree with those derived from the more fundamental effective approach, HB$χ$PT.

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W. P. Alvarez, K. Kubodera, F. Myhrer. 2005-09-02. Comparison of the extended linear sigma model and chiral perturbation theory. https://doi.org/10.1103/physrevc.72.038201

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