Shell effects in fusion of heavy nuclei

Conference · Wed Dec 31 04:00:00 EST 1997

OSTI ID:560241

Moeller, P ^[1]; Nix, J R ^[2]

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1. Moller Scientific Computing and Graphics, Inc., Los Alamos, NM (United States)
2. Los Alamos Natioal Lab., NM (United States)

The spontaneous-fission properties of Fm isotopes undergo dramatic changes between {sup 256}Fm and {sup 258} Fm. The fission fragments of the former isotope are mass asymmetric with kinetic energies of about 200 MeV, whereas the fission fragments of the latter isotope are symmetric with kinetic energies of about 235 MeV. This rapid change occurs because the division into nearly doubly magic fragments near {sup 132}Sn becomes possible and opens up new valleys in the fission potential-energy surface. In the cold-fusion reactions leading to the heaviest elements, the nearly doubly magic targets and/or projectiles may give rise to important features associated with this magicity. Cold fusion is thought to favor heavy-element formation because it leads to low excitation energies of the compound nuclei. We investigate how near-magic targets and projectiles may lead to persistent survivability of the shells in the fusion valley as the ions merge, in addition to their effect on the compound-nucleus excitation energy.

• OSTI ID: 560241
• Report Number(s): CONF-970443--
• Country of Publication: United States
• Language: English

Related Subjects

66 PHYSICS
COLD FUSION
COMPOUND NUCLEI
EXCITATION
FISSION FRAGMENTS
HEAVY NUCLEI
POTENTIAL ENERGY
PROJECTILES
SHELLS
SPONTANEOUS FISSION
TARGETS