Superheavy and hyperheavy nuclei in the form of bubbles or semi-bubbles

Self-consistent Hartree-Bogoliubov calculations have been performed with the effective interaction of Gogny for a large array of proton and nucleon numbers (120 less than or equal to Z less than or equal to 340; 300 less than or equal to A less than or equal to 1000). Solutions in the form of a bubble and of "unsaturated" nuclei ("semi-bubbles") with a reduced central density are found, which may be ground states or excited metastable configurations. Fission barriers and estimates of a-decay lifetimes are given for typical nuclei. (C) 1999 Elsevier Science B.V. All rights reserved.