Strange baryon spectra in a Bethe-Salpeter dynamical model

Abstract

A Bethe-Salpeter equation (BSE) has been derived using a covariant confining interaction motivated from QCD. Recently, this interaction has been applied to a qqq system under the null plane ansatz (NPA), which reduces the resulting equations to three-dimensional form. For equal mass quarks, encouraging results were obtained for baryon masses and quantum numbers. In the present paper, this formalism is generalized to unequal mass kinematics and applied to the spectroscopy of strange baryons (Λ, Σ, Ξ, Ω). All input parameters are fixed from previous calculations. The reduced qqq equation in the NPA is solved algebraically in a six-dimensional harmonic oscillator basis, on lines analogous to the corresponding techniques developed for the equal mass qqq problem. The results on the Λ, Σ spectra are in good agreement with data, where available, up to levels N=5. Our results are compared with those from another relativized potential of baryon masses.