Resonances, Chiral Symmetry, Coupled Channel Unitarity and Effective Lagrangians

TL;DR

This paper uses a coupled channel unitarity approach to extend chiral perturbation theory, successfully reproducing low-lying meson resonances up to 1.2 GeV and exploring implications for meson spectroscopy.

Contribution

It demonstrates how non-perturbative unitarity methods can extend chiral perturbation theory to higher energies, reproducing meson resonances with established Lagrangian parameters.

Findings

Reproduces meson resonances up to 1.2 GeV

Extends chiral perturbation theory to higher energies

Provides insights into meson spectroscopy

Abstract

By means of a coupled channel non-perturbative unitary approach, it is possible to extend the strong constrains of Chiral Perturbation Theory to higher energies. In particular, it is possible to reproduce the lowest lying resonances in meson-meson scattering up to 1.2 GeV using the parameters of the O(p^2) and O(p^4) Chiral Lagrangian. We report on an update of these results examining their possible relevance for meson spectroscopy.