Chiral dynamics of many-pion systems

TL;DR

This paper models the chiral dynamics of many-pion systems using the Weinberg and hidden local symmetry Lagrangians, providing new insights into rho and omega decays and matching recent experimental data.

Contribution

It introduces a novel theoretical framework for describing multi-pion decays and calculates decay widths and resonance excitation curves for the first time.

Findings

Excitation curves of rho resonance in 4 pi decay obtained for the first time.

Partial widths of omega decays to multiple pions evaluated for the first time.

Comparison with CMD-2 data validates the theoretical approach.

Abstract

Based on the Weinberg lagrangian or, in a new language, the lagrangian of hidden local symmetry added with the term induced by the anomalous lagrangian of Wess and Zumino, the dynamics of the decays rho to 4 pi and omega to 5 pi is considered. The excitation curves of rho resonance in its decay to 4 pi are obtained for the first time. The comparison with recent CMD-2 data is given. The partial widths of the decays omega to 2 pi^+ 2 pi^- pi^0 and omega to pi^+ pi^- 3 pi^0 which can be measured on colliders with luminosity 10^{33}{cm }^{-2}{s}^{-1} are evaluated for the first time.