A new exact microscopic multiphonon approach to the nuclear eigenvalue problem

We propose a method for deriving a set of eigenvalue equations within a subspace spanned by states which are tensor products of nn Tamm–Dancoff phonons. Recursive relations allow to one solve these equations iteratively, starting from the particle–hole vacuum, and, thereby, to generate a basis of microscopic multiphonon states. The Hamiltonian has a simple spectral decomposition in such a basis and can be easily brought into diagonal form. 16O is chosen as testing ground for the method.