An observation of the $f_0(1710)$ meson in the $ωϕ$ system in the Pion-$Be$ Interaction at Momentum of 29 GeV
The charge-exchange reaction $π^-p \rightarrow n\,ω(783)ϕ(1020)$, $ω\rightarrow π^+π^-π^0$, $ϕ\rightarrow K^+K^-$ is studied with the upgraded VES facility (U-70, Protvino) in the interaction of a 29 GeV pion beam with a beryllium target. The distribution over the invariant mass of the system $M_{ωϕ}$ shows a near-threshold signal. A partial wave analysis reveals that the scalar state ($J^{PC}=0^{++}$) dominates in this mass region. The observed signal can be described with a contribution of the known resonance $f_0(1710)$. Using OPE approximation for the reaction $π^-p \rightarrow n\, f_0(1710)$ the product of branching fractions is found to be: $Br(f_0(1710)\rightarrow ππ)\cdot Br(f_0(1710)\rightarrow ωϕ) = (4.8 \pm 1.2) \cdot 10^{-3}$.
hep-ex↗