Testing factorization in color-suppressedb-flavor decays with theB→ηc+K(K*) modes

The discrepancy recently observed between B→J/ψ+K(${\mathit{K}}^{\mathrm{*}}$) data and commonly used hadronic form factor models might be due to a breakdown of the factorization assumption. By showing that the B→${\mathrm{\eta }}_{\mathit{c}}$+K(${\mathit{K}}^{\mathrm{*}}$) rates can be calculated without using any particular form factor model, we propose a test of the factorization hypothesis. This test is free of possible uncertainties caused by W-exchange graph contributions. If factorization holds, the measurable ratio Γ(B→${\mathrm{\eta }}_{\mathit{c}}$+${\mathit{K}}^{\mathrm{*}}$)/Γ(B→${\mathrm{\eta }}_{\mathit{c}}$+K) is predicted to be in the range from 0.18 to 0.95 when the CLEO II data on B→J/ψ+K(${\mathit{K}}^{\mathrm{*}}$) are used.