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Abstract: The damping of collective rotational motion is investigated by means of particles-rotor model in which the angular momentum coupling is treated exactly and the valence nucleons are in a multi-j shell mean-field. It is found that the onset energy of rotational damping is around 1.1 MeV above yrast line, and the number of states which form rotational band structure is thus limited. The number of calculated rotational bands around 30 at a given angular momentum agrees qualitatively with experimental data. The onset of rotational damping takes place gradually as a function of excitation energy. It is shown that the pairing correlation between valence nucleons has a significant effect on the appearance of rotational damping. [Copyright &y& Elsevier]

A shape change of the self-consistent mean-field induced by a configuration change is discussed within the conventional constrained Hartree–Fock (CHF) theory. It is stressed that a single-particle level crossing dynamics should be treated carefully, because the shape of the mean-field in such a finite many-body system as the nucleus strongly changes depending on its configuration. This situation is clearly shown by applying an adiabatic assumption, where the most energetically favorable single-particle states are assumed to be occupied. The excited HF states and the continuously-connected potential energy curves are given by applying the configuration dictated CHF method. The effect of pairing correlation is discussed in the level crossing region. Triaxial deformed results in our Hartree–Fock–Bogoliubov (HFB) calculation with Gogny force nicely reproduce the available experimental data of Ge isotopes. From our numerical calculation, it is concluded that the CHFB state is more fragile than the CHF state in the level crossing region. [Copyright &y& Elsevier]

Abstract: Rotational bands of 253No and 251Md are studied by the cranked shell model with particle-number conserving treatment for monopole and quadrupole pairing correlations. Observed bands are reproduced very well by theoretical results. A backbending of kinematic moment of inertia is predicted at in bands of 253No. This is attributed to the simultaneous alignment of neutron and proton pairs. Only one signature band was observed in 251Md. We predict its signature partner band with a sharp backbending at very low frequency of . Backbendings of in 251Md are the consequence of crossing between the proton and configurations. The sudden rise of is mainly due to the large alignment of proton pair. [Copyright &y& Elsevier]

The projected shell model is used to study the multi-quasiparticle and collective excitations of 178Hf. With an axially symmetric basis, the spin-16 isomer at 2.4 MeV appears to be well separated in energy/spin space from other configurations. However, projected energy surface calculations suggest that 178Hf has significant softness to axially asymmetric shapes, which can strongly modify the level distribution. The implications for photodeexcitation of the isomer are discussed. [Copyright &y& Elsevier]

A modified method for calculating the pion vacuum susceptibility from an effective quark–quark interaction model is derived. Within this approach it is shown that the pion vacuum susceptibility is free of ultraviolet divergence and is much smaller than the previous estimations. [Copyright &y& Elsevier]

Abstract: At finite temperature systems with the hyperon-hyperon(YY) interactions are investigated within the framework of the RMFT. With the weak YY interaction, the maximum strangeness content for bound strange hadronic matter decreases with the increase of temperature, if the temperature exceeds 21MeV, strange hadronic matter does not have bound state, while with the strong YY interaction the highest temperature is 30MeV. There is a highest temperature limit(40MeV) for stable neutron stars, which is independent on the choose of the YY interactions. The maximum mass with the weak YY interaction () is consistent with the mass constraint. [Copyright &y& Elsevier]