Evidence for f0(980)f0(980) production in chi_c0 decays

Abstract

Using a sample of 14 million $ψ(2S)$ events accumulated with the BES II detector, evidence for $f_0(980)f_0(980)$ production in $χ_{c0}$ decays is obtained for the first time; the branching ratio is determined to be ${\cal B}(χ_{c0}\to f_0(980)f_0(980)\toπ^+π^-π^+π^-) = (7.6 \pm 1.9 ({\rm stat}) \pm 1.6 ({\rm syst})) \times 10^{-4}$. The significance of the $f_0(980)$ signal is about 4.6$σ$.