New insights from studies of spontaneous fission with large detector arrays

Termination of rotational bands: disappearance of quantum many-body collectivity

Rotational bands in the mass 100 region

Covariant description of shape evolution and shape coexistence in neutron-rich nuclei at N≈60

Nuclear Data Sheets for A = 84

The occurrence of highly deformed nuclei in the A approximately=80 and A approximately=100 mass regions has been investigated in the framework of the Strutinsky approach with a Nilsson-type potential and the Yukawa-plus-exponential macroscopic mass formula, including elongation, necking and gamma deformation. Special emphasis was given to the spin-orbit potential parameters, which have large variations at the magic numbers and also depend on the shell filling. Good reproduction of the masses, deformations and shape transition was achieved in both mass regions. The phenomena of shape coexistence are also supported by the calculated potential energy surfaces. The odd-particle influence in driving the nucleus to deformed shapes is demonstrated. The results obtained are rather similar to those of the more elaborated Yukawa shell-model calculations, and show for the first time that a Nilsson-type model can also account for the large deformations of the light Kr, Sr and Zr nuclei.

D Galeriu

Papers

Nuclear deformations in the A≈80-100 region