2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/193000We investigate the isospin-violating mixing of the light scalar mesons a0(980) and f0(980) within the unitarized chiral approach. Isospin-violating effects are considered to leading order in the quark mass differences and electromagnetism. In this approach both mesons are generated through meson-meson dynamics. Our results provide a description of the mixing phenomenon within a framework consistent with chiral symmetry and unitarity, where these resonances are not predominantly q q-bar states. Amongst the possible experimental signals, we discuss observable consequences for the reaction J/Psi -> phi pi0 eta in detail. In particular we demonstrate that the effect of a0-f0 mixing is by far the most important isospin-breaking effect in the resonance region and can indeed be extracted from experiment.15 pages, 9 figures; discussion extended, title changed, version published in Phys. Rev. DHigh Energy Physics - PhenomenologyHigh Energy Physics - ExperimentNuclear Theorytext