Relativistic chiral representation of the $\pi N$ scattering amplitude I: The Goldberger-Treiman relation

Abstract

In this work we study the $\pi N$ scattering process within the Baryon Chiral Perturbation Theory framework in the covariant scheme of Extended-On-Mass-Shell (EOMS). We compare the description obtained in this scheme with the previously obtained using the Infrared Regularization scheme and show that EOMS accomplishes the best convergence, being able to extract from partial wave analyses reliable values of important quantities as the Goldberger-Treiman deviation. In regard to the latter, we solve the long-standing problem concerning to the extraction of the Goldberger-Treiman deviation with covariant ChPT that jeopardized the applicability of ChPT to the $\pi N$ system. We also show the potential of the unitarization techniques applied to the perturbative calculation in the EOMS scheme, that allow us to increase the range of validity of our description up to $\approx 200$ MeV in $\sqrt{s}$.

PROCEEDINGS to the 33rd International School of Nuclear Physics "From Quarks and Gluons to Hadrons and Nuclei"- 7 Pag,, 1 Table, 4 Figures. Erice-Sicily: 16 - 24 September 2011

References in corpus (4)

• Extended Partial-Wave Analysis of piN Scattering Data
• The chiral representation of the $\pi N$ scattering amplitude and the pion-nucleon sigma term
• Leading SU(3)-breaking corrections to the baryon magnetic moments in Chiral Perturbation Theory
• πN scattering in relativistic baryon chiral perturbation theory revisited