V. P. Sugonyaev | Searcharxiv

arXiv2024

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↗

arXiv1997

Study of the $ηπ^o$ system in the mass range up to 1200 MeV

The reaction $π^-p \to ηπ^o n$ has been studied with GAMS-2000 spectrometer in the secondary 38 GeV/c $π^-$-beam of the IHEP U-70 accelerator. Partial wave analysis of the reaction has been performed in the $ηπ^o$ mass range up to 1200 MeV. The $a_0(980)$-meson is seen as a sharp peak in S-wave. The $t$-dependence of $a_0(980)$ production cross section has been studied. Dominant production of the $a_0(980)$ at a small transfer momentum $t$ confirms the hypothesis of Achasov and Shestakov about significant contribution of the $ρ_2$ exchange ($I^GJ^{PC}=1^+2^{--}$) in the mechanism of $a_0(980)$ meson production in $t$-channel of the reaction.

hep-ex↗