Eur. Phys. J. A (2008) 37: 233-243
https://doi.org/10.1140/epja/i2008-10625-3

Regular Article — Theoretical Physics

The N^*(1710) as a resonance in the ππN system

Departamento de Física Teórica and IFIC, Centro Micto Universidad de Valencia-CSIC, Institutos de Investigación de Paterna, Aptdo. 22085, 46071, Valencia, Spain

^* e-mail: kanchan@ific.uv.es

Received: 5 May 2008
Revised: 15 July 2008
Published online: 12 August 2008

Abstract

We study the ππN system by solving the Faddeev equations, for which the input two-body t-matrices are obtained by solving the Bethe-Salpeter equation in the coupled-channel formalism. The potentials for the ππ, πN sub-systems and their coupled channels are obtained from chiral Lagrangians, which have been earlier used to study resonances in these systems successfully. In this work, we find a resonance in the ππN system with a mass of 1704 − i375/2MeV and with quantum numbers I = 1/2, J ^π = 1/2⁺. We identify this state with the N ^*(1710). This peak is found where the energies of the ππ sub-system fall in the region of the σ-resonance. We do not find evidence for the Roper resonance in our study indicating a more complex structure for this resonance, nor for any state with total isospin I = 3/2 or 5/2.