Convergence properties of η → 3π in low energy QCD

Abstract

Even today, the convergence of the decay widths and some of the Dalitz plot parameters of the η→3π decays seems problematic in low energy QCD. We provide an overview of the current experimental and theoretical situation with historical background and summarize our recent results, which explore the question of compatibility of experimental data with a reasonable convergence of a carefully defined chiral series in the framework of resummed chiral perturbation theory.