The effect of multi-channel pion-pion scattering in decays of the ${\rm Y}$-family mesons

Yu. S. Surovtsev, P. Bydzovsky, T. Gutsche +3

The effect of isoscalar S-wave multi-channel pion-pion scattering ($\pi \pi \to \pi \pi ,K\bar{K},\eta \eta$) is considered in the analysis of data on decays of the ${\rm Y}$-meson family -- $Υ(2S)\toΥ(1S)π…