“…in the meson loops) plays a role in other isospin breaking processes. This effect, known to be of particular importance near the continuum thresholds, was already studied in the η ′ decays [20], and in the decays φ → ωπ 0 [21,22], J/ψ → φηπ 0 [23,24], and D s0 (2317) → D s π 0 [25,26,27].…”