First implementation of the MPMH formalism in nuclear physics

The theoretical description of the various states of a nucleus with A nucleons is given by the Schroedinger equation. Despite today's power of computers, the resolution of such an equation is limited to a few low values of A. For years another strategy has been developed to deal with all nuclei in which it is assumed that nucleons interact with a mean field independently from other nucleons. The last methods that have been developed are the self-consistent configuration-mixing approaches and particularly the multiparticle-multi-hole configuration method (MPMH). The MPMH allows the conservation of the number of particles as well as the total angular momentum and complies strictly with Pauli's principle. The MPMH method can be used for all nucleus whatever the parity of the number of protons/neutrons. The standard state is defined as the Slater determinant (DS) in which nucleons are set on the lowest energy shells. MPMH consists in describing the states of the nucleus as a superposition of DS built by promoting M particles on higher energy shells while generating M holes. The wave function corresponding to this description of the nucleus nears the exact solution. (A.C.)