par Descouvemont, Pierre
Référence European Physical Journal A. Hadrons and Nuclei, 57, 1, 29
Publication Publié, 2021-01-01
Article révisé par les pairs
Résumé : We discuss resonance properties in three-body systems, with examples on 12C and 24Mg. We use a microscopic cluster model, where the generator coordinate is defined in the hyperspherical formalism. The 12C nucleus is described by an α+ α+ α structure, whereas 24Mg is considered as an 16O + α+ α system. We essentially pay attention to resonances. We review various techniques which may extend variational methods to resonances. We consider 0 + and 2 + states in 12C and 24Mg. We show that the r.m.s. radius of a resonance is strongly sensitive to the variational basis. This has consequences for the Hoyle state (02+ state in 12C) whose radius has been calculated or measured in several works. In 24Mg , we identify two 0 + resonances slightly below the three-body threshold.