Influence of Nuclear Structure on Decay Properties of Heavy Nuclei

Sammanfattning: This dissertation deals with the effects of nuclear structure on the α-decay properties, and on the fission-yielddistributions from the decay of heavy nuclei. The nuclear-structure and decay properties of superheavynuclei is one of the central topics for investigation. α decay is treated in a microscopic approach employingSkyrme-Hartree-Fock-Bogoliubov wave functions to describe the formation of an α cluster in the unstablenucleus. Fission is treated using the random-walk approach, where the nuclear level density obtained from adetailed model influences the dynamical evolution of the shape of the nucleus. The dissertation contains fiveoriginal research papers, and an introductory part containing background information and some additionaldetails of the studies.Paper I contains an investigation of the α-particle formation amplitudes and decay rates obtained withSkyrme-Hartree-Fock-Bogoliubov wave functions for even-even near-spherical nuclei.Paper II contains a study of some more aspects of the description in Paper I.Paper III extends the application of the method in papers I and II to odd-mass near-spherical nuclei.Hindrance factors and the competition between α-decay paths to different excited states are investigated.Paper IV deals with the theoretical description of low-lying states in superheavy nuclei observed in α-decay and spectroscopy measurements on element 115 decay chains.Paper V contains results for fission-yield distributions obtained by combining the nuclear level densitiesfrom a combinatorial model with the five-dimensional shape space random-walk approach. The influence on theyields from the structure of the microscopically calculated level densities is investigated.