A new decay mode of higher charmonium

Abstract

Abstract We calculate the $$\Lambda _c{\bar{\Lambda }}_c$$ ΛcΛ¯c partial decay width of the excited vector charmonium states around 4.6 GeV with the quark pair creation model. We find that the partial decay width of the $$\Lambda _c{\bar{\Lambda }}_c$$ ΛcΛ¯c mode can reach up to several MeV for $$\psi (4S,~5S,~6S)$$ ψ(4S,5S,6S) . In contrast, the partial $$\Lambda _c{\bar{\Lambda }}_c$$ ΛcΛ¯c decay width of the states $$\psi (3D,~4D,~5D)$$ ψ(3D,4D,5D) is less than one MeV. If the enhancement Y(4630) reported by the Belle Collaboration in $$\Lambda _c{\bar{\Lambda }}_c$$ ΛcΛ¯c invariant-mass distribution is the same structure as Y(4660), the Y(4660) resonance is most likely to be a S-wave charmonium state.