Fission Properties of Neutron-Rich Nuclei around the End Point of r-Process

We studied the fission properties of neutron-rich nuclei Cf-278,Cf- 286 around the end point of r-process by microscopic self-consistent approaches. The fission barriers and potential energy surfaces are obtained by constrained static Skyrme Hartree-Fock-BCS calculations. Fission fragments are studied by dynamical time-dependent Hartree-Fock+BCS calculations. Results show that Cf-286 has an octupole deformation at ground state, which can increase the fission barrier height by 1.1 MeV and enhance significantly the spontaneous fission half-life. To search possible fission channels, dynamical calculations with a broad coverage of initial deformations result in two slightly asymmetric peaks around A = 128 and 150 for Cf-278, and A = 133 and 153 for Cf-286. Very asymmetric fission channels as given by semi-empirical models are not found in our results.

Automated summary

The fission properties of neutron-rich nuclei Cf-278 and Cf-286 near the end point of the r-process are studied using microscopic self-consistent approaches. Fission barriers and potential energy surfaces are obtained through constrained static Skyrme Hartree-Fock-BCS calculations. Fission fragments are studied through dynamical time-dependent Hartree-Fock+BCS calculations. The results show that Cf-286 has an octupole deformation at the ground state, which can increase the fission barrier height and significantly enhance the spontaneous fission half-life. No very asymmetric fission channels predicted by semi-empirical models are found in our results.