Exclusive decay of $Υ$ into $J/ψ+χ_{c0,1,2}$

Abstract

We study the $Υ$ exclusive decay into double charmonium, specifically, the $S$-wave charmonium $ J/ψ$ plus the $P$-wave charmonium $χ_{c0,1,2}$ in the NRQCD factorization framework. Three distinct decay mechanisms, i.e., the strong, electromagnetic and radiative decay channels are included and their interference effects are investigated. The decay processes $Υ(1S,2S,3S)\to J/ψ+χ_{c1,0}$ are predicted to have the branching fractions of order $10^{-6}$, which should be observed in the prospective Super $B$ factory.

22 pages, 9 figures, 3 tables