Long distance effects in b→ s exclusive decays.

We estimate long distance corrections to radiative B → Kγ and to non leptonic B→ Kπ, B→ Kπ, B→ Kσ, B→ Kσ, B→ KΦ and B→ KΦ decays generated by the ( $$\overline b$$ c) ( $$\overline c$$ s) part of the non leptonic weak Hamiltonian. While vanishing in the vacuum saturation approximation, these corrections are finite if one includes single particle charmed states between the currents in the Hamiltonian. We find small effects in radiative decays, but significant contributions to several non leptonic processes. [ABSTRACT FROM AUTHOR]