13.12.10 16:15
Alternative interaction potentials in a covariant Bethe-Salpeter quark model for the nonstrange-strange baryon sector
Michael Ronniger (Bonn)
The description of the hadronic resonance spectrum is still a challenging issue in strong interaction physics. A quark model for baryons, developed in the past decade by U. Löring et al., based on the Bethe-Salpeter-equation can account for many prominent features in the baryon sector. The model is fully relativistic, covariant and CPT-invariant. With a linear rising quark-quark potential together with an instanton induced 't Hooft force a reasonable description of the mass-spectra in the non-strange and strange baryonsector up to masses of roughly 3 GeV was obtained. However, there are still specific problems with the position of some resonances, e.g. the conspicuous low position of the lowest negative parity Lambda-resonance and some excited Delta states.
I will present how to implement an alternative description of the confinement potential as well as an alternative flavour dependent interaction motivated by pseudoscalar meson exchange. I will discuss the consequences for the mass spectra with particular emphasis on the probelematic states.
(Seminarraum II)