Search for charmonium and charmoniumlike states in γ(2S) radiative decays

Using a sample of 158 × 10⁶ γ(2S) events collected with the Belle detector, charmonium and charmoniumlike states with even charge parity are searched for in γ(2S) radiative decays. No significant XcJ or η_c signal is observed, and the following upper limits at 90% confidence level (C. L.) are obtained: B(γ(2S) γX_c0)< 1:0 × 10^-4, B(γ(2S) γX_c1) < 3:6 × 10^-6, B(γ(2S) γX_c2) < 1:5 × 10^-5, and B(γ(2S) γη_c) < 2:7 × 10^-5. No significant signal of any charmoniumlike state is observed, and we obtain the limits B(γ(2S) γX(3872)) X B(X(3872) π⁺π^- J/ψ)<0.8 × 10^-6, B(γ(2S) γX(3872))X B(X(3872) π⁺π^-π⁰J/ψ)<2:4 × 10^-6, B(γ(2S) γX(3915)) X B(X(3915) ωJ/ψ)<2:8 × 10^-6, B(γ(2S) γY(4140)) X B(Y(4140) ΦJ/ψ)) < 1:2 × 10^-6, and B(γ(2S) γX(4350)) X B(X(4350) ΠJ/ψ) < 1:3 × 10^-6 at 90% C. L.