OCTET AND DECUPLET BARYONS IN A COVARIANT AND CONFINING DIQUARK-QUARKMODEL

The baryon octet and decuplet masses and Bethe-Salpeter vertex and wav e functions are calculated in the ladder approximation to the quark ex change between a scalar or axialvector diquark and a constituent quark . These functions reflecting full Lorentz covariance are given in term s of an expansion in Gegenbauer polynomials. In the rest frame of the baryon, a complete partial wave decomposition of the Bethe-Salpeter wa ve function is performed. The confinement of quarks and diquarks is im plemented via a parametrization of the corresponding propagators. We a lso discuss some aspects of the momentum routing in the ladder approxi mation to the Bethe-Salpeter equation. Numerical results for the octet and decuplet masses with broken flavor SU(3) in the conserved isospin limit are presented. [S0556-2813(98)00810-3].