πN-->ηN and ηN-->ηN partial-wave T matrices in a coupled, three-channel model
Abstract
The πN-->ηN and ηN-->ηN partial-wave T matrices for the eight lowest partial waves have been obtained in a three-coupled-channel model with unitarity manifestly imposed. The two physical channels are πN and ηN, and the third channel, ππN is an effective, but unphysical two-body channel which represents all remaining processes. The πN elastic phase shifts and the weighted data base of the πN-->ηN total and differential cross sections are chosen as the input for the fitting procedure. A model containing a single resonance in each of the three partial waves that dominates the η production at lower energies is compared with previous analyses, based on similar assumptions. A multiresonance coupled-channel model is introduced which significantly improves the agreement with all input data. Our results are compared with a complementary multiresonance coupled-channel analysis that is constrained with elastic and continuum production channels. The inclusion of the fourth P11 resonance in the 1440-2200 MeV region further improves the agreement between the analysis and the data.
- Publication:
-
Physical Review C
- Pub Date:
- May 1995
- DOI:
- 10.1103/PhysRevC.51.2310
- arXiv:
- arXiv:nucl-th/9501011
- Bibcode:
- 1995PhRvC..51.2310B
- Keywords:
-
- 25.40.Ve;
- 13.75.Gx;
- 14.40.Aq;
- 24.10.Eq;
- Other reactions above meson production thresholds;
- Pion-baryon interactions;
- pi K and eta mesons;
- Coupled-channel and distorted-wave models;
- Nuclear Theory;
- High Energy Physics - Phenomenology
- E-Print:
- PostScript figures now included, revtex, 28 pages + 6 figures (gzip + uuencode) submitted to Phys. Rev. C