Disentangling the dynamical origin of P11 Nucleon Resonances

Abstract

We show that two almost degenerate poles near the $πΔ$ threshold and the next higher mass pole in the $P_{11}$ partial wave of $πN$ scattering evolve from a single bare state through its coupling with $πN$, $ηN$ and $ππN$ reaction channels. This finding provides new information on understanding the dynamical origins of the Roper $N^*(1440)$ and $N^*(1710)$ resonances listed by Particle Data Group. Our results for the resonance poles in other $πN$ partial waves are also presented.

Improved version, accepted Phys. Rev. Lett