Microscopic study of nuclear level densities and thermodynamical properties in 170,171,172Yb

The nuclear level density and entropy were extracted for 170,171,172Yb isotopes within microscopic theory, which includes nuclear pairing interaction. The calculations were based on the modified harmonic oscillator according the Nilsson potential for deformed nuclei. From the level densities, thermodynamical quantities such as temperature and entropy have been deduced. The entropies of the neutron hole and particle are estimated from the entropy difference between the odd-mass and even–even nuclei. The critical temperature of the pair-breaking process is found to be Tc ~ 0.4–0.5 MeV. The results were compared with experimental data obtained by the Oslo group.