2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/40236The bound-state Schwinger-Dyson and Bethe-Salpeter (SD-BS) approach is chirally well-behaved and provides a reliable treatment of the eta-eta' complex although a ladder approximation is employed. Allowing for the effects of the SU(3) flavor symmetry breaking in the quark-antiquark annihilation, leads to the improved eta-eta' mass matrix.11 pages, 1 figure, revtex. Invited talk presented by D. Klabucar at the workshop "Quark Matter in Astro- and Particle Physics" (27.-29. November 2000, Rostock, Germany), to appear in the proceedings of this workshopHigh Energy Physics - PhenomenologyNuclear Theorytext