Non-Factorization in $(B, B_s) \to P(V) \psi$ Decays

Available experimental data on decay rate and polarization are used to investigate non-factorization contribution to processes of the kind $B \rightarrow K \psi$, and $B \rightarrow K^* \psi$ using five theoretical models for the formfactors. Using the knowledge on non-factorization gained from $B$ decays we study the processes $B_s \rightarrow (\eta', \eta) \psi$, and $B_s \rightarrow \phi \psi$ where experimental data are very limited.