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Octet and Decuplet Baryons in a Covariant and Confining Diquark-Quark Model

M. Oettel·G. Hellstern·R. Alkofer·H. Reinhardt
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Abstract

The baryon octet and decuplet masses and Bethe-Salpeter vertex and wave functions are calculated in the ladder approximation to the quark exchange between a scalar or axialvector diquark and a constituent quark. These functions reflecting full Lorentz covariance are given in terms of an expansion in Gegenbauer polynomials. In the rest frame of the baryon, a complete partial wave decomposition of the Bethe-Salpeter wave function is performed. The confinement of quarks and diquarks is implemented via a parametrisation of the corresponding propagators. We also discuss some aspects of the momentum routing in the ladder approximation to the Bethe-Salpeter equation. Numerical results for the octet and decuplet masses with broken flavour SU(3) in the conserved isospin limit are presented.

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M. Oettel, G. Hellstern, R. Alkofer, H. Reinhardt. 1998-07-10. Octet and Decuplet Baryons in a Covariant and Confining Diquark-Quark Model. https://doi.org/10.1103/physrevc.58.2459

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