Search for charmonium and charmoniumlike states in Υ(1S) radiative decays

Using a sample of 102×10⁶ Υ(1S) events collected with the Belle detector, we report on the first search for charge-parity-even charmonium and charmoniumlike states in Υ(1S) radiative decays. No significant χ_cJ or η_c signal is observed and 90% C.L. limits on B(Υ(1S)→γχ_c0)<6.5×10^-4, B(Υ(1S)→γχ_c1)<2.3×10^-5, B(Υ(1S)→γχ_c2)<7.6×10^-6, and B(Υ(1S)→γη_c)<5.7×10^-5 are obtained. The product branching fraction limits B(Υ(1S)→γX(3872))B(X(3872)→π⁺π^-J/ψ)<1.6×10^-6, B(Υ(1S)→γX(3872))B(X(3872)→π⁺π^-π⁰J/ψ)<2.8×10^-6, B(Υ(1S)→γX(3915))B(X(3915)→ωJ/ψ)<3.0×10^-6, and B(Υ(1S)→γY(4140))B(Y(4140)→ϕJ/ψ)<2.2×10^-6 are obtained at the 90% C.L. Furthermore, no evidence is found for excited charmonium states below 4.8GeV/c².