Two nucleon induced Lambda decay in nuclei.

The pionic channel of Λ decay in nuclei is forbidden by the Pauli principle. We discuss the decay in another state, the pion branch, a collective state which is a coherent nuclear stperposition of pionic and Δ-h state and which lies at an energy lower than the physical pion. Its decay mode in the region concerned here is by two-particle emission. The Λ decay process is then a two-nucleon induced one: Λ+p+n→p+n+n. We find a sizeable branching ratio.