Vers une description unifiée de la structure nucléaire: Modèles IBM, IBFM et supersymétries

This article is a review of the models introduced recently for the description of low-lying collective states in nuclei in terms of interacting bosons. The general basic ideas underlying the IBM (even-even nuclei) and IBFM (odd-even nuclei) models are first given, outlining some simple analytical results obtained using group theory. The theoretical predictions are compared with selected experimental data and the successes and limitations of these models are briefly discussed. The more recent supersymmetry model, which attempts to unify the description of even-even and odd-even nuclei within the same theoretical framework, is then introduced and existing experimental tests of it are discussed.