Pion-nucleon scattering inside the Mandelstam triangle
High Energy Physics - Phenomenology
2009-10-31 v1 Nuclear Theory
Abstract
We study the third order pion-nucleon scattering amplitude obtained from heavy baryon chiral perturbation theory inside the Mandelstam triangle. We reconstruct the pion-nucleon amplitude in the unphysical region by use of dispersion relations and determine the pertinent low-energy constants by a fit to this amplitude. A detailed comparison with values obtained from phase shift analysis is given. Our analysis leads to a pion-nucleon sigma-term of sigma(0) = 40 MeV based on the Karlsruhe partial wave analysis. We have repeated the same procedure using the latest solution of the VPI group and find a much larger value for sigma(0).
Cite
@article{arxiv.hep-ph/9908247,
title = {Pion-nucleon scattering inside the Mandelstam triangle},
author = {Paul Büttiker and Ulf-G. Meißner},
journal= {arXiv preprint arXiv:hep-ph/9908247},
year = {2009}
}
Comments
17 pp, LaTeX2e, 4 figs