New insights on low energy πn scattering amplitudes: Comprehensive analyses at O(p3)level
A production representation of partial-wave S matrix is utilized to construct low-energy elastic pion-nucleon scattering amplitudes from cuts and poles on complex Riemann sheets. Among them, the contribution of left-hand cuts is estimated using the results obtained in covariant baryon chiral perturb...
| Autores: | , , |
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| Tipo de recurso: | artículo |
| Estado: | Versión publicada |
| Fecha de publicación: | 2019 |
| País: | España |
| Institución: | Consejo Superior de Investigaciones Científicas (CSIC) |
| Repositorio: | DIGITAL.CSIC. Repositorio Institucional del CSIC |
| OAI Identifier: | oai:digital.csic.es:10261/207059 |
| Acceso en línea: | http://hdl.handle.net/10261/207059 |
| Access Level: | acceso abierto |
| Palabra clave: | Dispersion relations pion-nucleon scattering Chiral perturbation theory |
| Sumario: | A production representation of partial-wave S matrix is utilized to construct low-energy elastic pion-nucleon scattering amplitudes from cuts and poles on complex Riemann sheets. Among them, the contribution of left-hand cuts is estimated using the results obtained in covariant baryon chiral perturbation theory within the extended-on-nass-shell scheme. By fitting to data on partial-wave phase shifts, it is indicated that the existences of hidden poles in S and P channels, as conjectured in our previous paper [Eur. Phys. J. C, 78(7): 543 (2018)], are firmly established. Specifically, the pole mass of the S hidden resonance is determined to be (895±81)-(164±23)i MeV, whereas, the virtual pole in the P channel locates at (966±18) MeV. It is found that analyses at the level improves significantly the fit quality, comparing with the previous one. Quantitative studies with cautious physical discussions are also conducted for the other S- and P-wave channels. |
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