Search for ηc(2S)→ωω and ωφ decays and measurements of χcJ→ωω and ωφ in ψ(2S) radiative processes

Using (2712± 14) × 10⁶ ψ(2S) events collected with the BESIII detector at the BEPCII collider, we search for the decays ηc(2S)→ωω and ηc(2S)→ωφ via the process ψ(2S)→γηc(2S). Evidence of ηc(2S)→ωω is found with a statistical significance of 3.2σ. The branching fraction is measured to be B(ηc(2S)→ωω)=(5.65±3.77( stat.)±5.32( syst.))×10⁻⁴. No statistically significant signal is observed for the decay ηc(2S)→ωφ. The upper limit of the branching fraction at the 90% confidence level is determined to be B(ψ(2S)→γηc(2S),ηc(2S)→ωφ)<2.24× 10⁻⁷. We also update the branching fractions of χcJ→ ωω and χcJ→ωφ decays via the ψ(2S)→γχcJ transition. The branching fractions are determined to be B(χc0→ωω)=(10.63±0.11±0.46)× 10⁻⁴, B(χc1→ωω)=(6.39±0.07±0.29)× 10⁻⁴, B(χc2→ωω)=(8.50±0.08±0.38)× 10⁻⁴, B(χc0→ωφ)=(1.18±0.03±0.05)× 10⁻⁴, B(χc1→ωφ)=(2.03±0.15±0.12)× 10⁻⁵, and B(χc2→ωφ)=(9.37±1.07±0.59)× 10⁻⁶, where the first uncertainties are statistical and the second are systematic.