Role of bare propagator poles in phenomenological Dyson-Schwinger type models

The generation of dressed meson-nucleon scattering-matrix poles is presented. A possible scenario for the interrelation of bare and dressed baryon poles is shown by using a particular version of coupled-channel Dyson-Schwinger type model. These findings are then applied to the Roper resonance, and the conclusion is drawn that it is dynamic in nature. A possible correlation between bare and dressed propagator poles on one side and the quantities of constituent quark-model calculations on the other side are discussed. (orig.)