Untersuchung der ersten Nukleonresonanzen in der Pion-Nukleon Streuung
Untersuchung der ersten Nukleonresonanzen in der Pion-Nukleon Streuung
In the present work we study the first excited states of the nucleon by investigating $\pi$N scattering from the threshold up to c.m, energies of 1.9 GeV. Therefore, we develop a meson exchange model which describes $\pi$N scattering in a system of the coupled reaction channels $\pi$N, $\sigma$N, $\...
| Personal Name(s): | Krehl, O. (Corresponding author) |
|---|---|
| Contributing Institute: |
Publikationen vor 2000; PRE-2000; Retrocat |
| Imprint: |
Jülich
Forschungszentrum Jülich, Zentralbibliothek, Verlag
1999
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| Physical Description: |
III, 145 p. |
| Document Type: |
Report Book |
| Research Program: |
Addenda |
| Series Title: |
Berichte des Forschungszentrums Jülich
3692 |
| Link: |
OpenAccess OpenAccess |
| Publikationsportal JuSER |
|
In the present work we study the first excited states of the nucleon by investigating $\pi$N scattering from the threshold up to c.m, energies of 1.9 GeV. Therefore, we develop a meson exchange model which describes $\pi$N scattering in a system of the coupled reaction channels $\pi$N, $\sigma$N, $\pi \Delta$, $\rho$N, $\pi$N*(1520), and $\eta$N. Within this model a detailed analysis of the resonance N*(1440) is performed. We find this resonance to be generated dynamically by the strong coupling to the $\sigma$N channel. By using the speedplot method resonance parameters are extracted. Within a simplified model we demonstrate, that the large inelasticity, which is connected with the resonance N*(1440), is generated by the often disregarded $\sigma$N channel and that the $\pi \Delta$ channel is less important. Furthermore, we investigate the resonance N*(1520). We find, that it is indeed possible to generate this resonance as $\rho$N bound state as suggested in earlier publications, but this is not in agreement with other observables. The importance of the resonance N*(1520) as a contribution to the differential cross section of the reaction $\pi$N $\rightarrow$ $\eta$N is seen as an interference, which leads to a strong angular dependence in this observable. |