Doorwayresonance model for pionnucleon D and Fwave scattering
Abstract
A model for the resonant pionnucleon D and Fwaves is developed which assumes that the pionplusnucleon couples to a resonance and that the resonance can serve as a doorway to the inelastic channels. With the use of simple form factors, the model is capable of reproducing the pionnucleon phase shifts up to an energy of T_{π} = 1.4 GeV if the coupling of the elastic channel to the inelastic channels is taken from data as input into the model. A value for the mass of the resonance that would result in the absence of the coupling to decay channels is extracted from the data utilizing the model. This is the mass that is most easily modeled by bag models. For the nonresonant D and Fwave channels a separable potential model is used. This model, like the resonance model, is developed utilizing the invariant amplitude which is free of kinematic singularities and uses invariant norms and phase spaces. The model is also applied to the Swave channels. A relation between the resonance model and the ChewLow model is discovered and used to derive an extended ChewLow model which is applied to the P _{13}, P _{31}, and P _{33} channels. Implications of the model for understanding the range of the pionnucleon interaction and the dynamic structure of the interaction are presented.
 Publication:

Nuclear Physics A
 Pub Date:
 November 1990
 DOI:
 10.1016/03759474(90)90184N
 Bibcode:
 1990NuPhA.518..658E