We analyze the ππ production amplitudes in the excited Υ decay processes, Υ (2S) → Υ (1S)π + π − , Υ (3S) → Υ (1S)π + π − and Υ (3S) → Υ (2S)π + π − , and the ππ and KK production amplitudes in the charmonium decay processes, ψ(2S) → J/ψπ + π − and J/ψ → φπ + π − , φK + K − . The amplitudes are parametrized by the sum of Breit-Wigner amplitudes for the σ and the other relevant particles and of the direct 2π-production amplitude, following the VMW method. All the ππ (and KK) invariant mass spectra are reproduced well with the σ Breit-Wigner amplitude by using the common parameters, mσ = 526 +48 −37 MeV and Γσ = 301 +145 −100 MeV, which is almost consistent with the values obtained in our previous phase shift analyses. This strongly suggests the existence of light σ-meson.
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