Chiral symmetry and parametrization of scalar resonances
| dc.creator | Arantes, L. O. | |
| dc.creator | Robilotta, M. R. | |
| dc.date | 2005-02-01 | |
| dc.date.accessioned | 2026-07-07T05:40:54Z | |
| dc.date.available | 2026-07-07T05:40:54Z | |
| dc.description | The linear $\s$-model is used to study the effects of chiral symmetry in unitarized amplitudes incorporating scalar resonances. When just a single resonance is present, we show that the iteration of a chiral tree amplitude by means of regularized two-pion loops preserves the smallness of $\p\p$ interaction at low energies and estimate the importance of pion off-shell contributions. The inclusion of a second resonance is performed by means of a chiral extension of the linear $\s$-model lagrangian. The new $\p\p$ ampitude at tree level complies with low-energy theorems, depends on a mixing angle and has a zero for a given energy between the resonance masses. The unitarization of this amplitude by means of two-pion loops preserves both its chiral low energy behavior and the position of this zero confirming, in a lagrangian framework, conclusions drawn previously by Törnqvist. Finally, we approximate and generalize our results and give a friendly expression that can be used in the parametrization of $N$ coupled scalar resonances. | |
| dc.description | 22 pages, 12 figures | |
| dc.identifier | https://arxiv.org/abs/nucl-th/0502001 | |
| dc.identifier | http://arxiv.org/abs/nucl-th/0502001 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/82396 | |
| dc.subject | Nuclear Theory | |
| dc.title | Chiral symmetry and parametrization of scalar resonances | |
| dc.type | text |