부산대학교 도서관

Fission barriers in nuclei belonging to the uranium region and their other characteristics are calculated on the basis of the FaNDF energy density functional. In particular, the neutron-separation energies S and S , the proton-separation energies S , and the beta-transition energies Q are calculated for uranium, neptunium, and plutonium isotopes. In addition, the deformation energies and parameters of these nuclei are presented along with their radii. A comparison with the predictions of the Skyrme-Hartree-Fock method implemented with several versions of the Skyrme energy density functionals is performed. The role of the octupole deformation β is studied for the U nucleus. It is shown that this deformation does not have any significant effect on the first-barrier height B or ground-state properties. At the same time, the second-barrier height B(2) f decreases by a factor of about two upon taking into account β . A phase transition at A ~ 260 is found for the three isotopic chains being considered: this point is a bifurcation point at which B (A) forks into two curves. Of these, the curve B (A) splits from it, prolonging the former curve for B (A) almost continuously, whereas the curve for B (A) itself goes down sharply. [ABSTRACT FROM AUTHOR]