Rotational properties of ${}^{252,253,254}$No. Influence of pairing correlations

Abstract

Rotational bands of ${}^{252,253,254}$No and the fission barriers of ${}^{254}$No at spin 0$\hslash$ and 20$\hslash$ are calculated with the Hartree-Fock-Bogolyubov theory and the Lipkin-Nogami approximate particle number projection. The SLy4 Skyrme force is used in the particle-hole channel. A zero-range force with and without density-dependence is used in the particle-particle channel. The experimental ground state deformation (${\mathcal{Q}}_{20}$ = 32.8 b) is reproduced as well as the increase of the dynamical moment of inertia with frequency both for ${}^{252}$No and ${}^{254}$No. The rotational band of ${}^{253}$No is also calculated. Fission barriers of ${}^{254}$No at spin 0$\hslash$ and 20$\hslash$ show the robustness of shell-corrections against rotation in these heavy nuclei.

Comments: 19 pages, 10 figures, Latex file