Xian-Rong Zhou

Nuclear structure of 178Hf related to the spin-16, 31-year isomer

The projected shell model is used to study the multi-quasiparticle and collective excitations of Hf-178. 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 Hf-178 has significant softness to axially asymmetric shapes, which can strongly modify the level distribution. The implications for photodeexcitation of the isomer are discussed

Protoneutron stars in the Brueckner-Hartree-Fock approach and finite-temperature kaon condensation

National Natural Science Foundation of China [10605018, 10905048, 10975116]; Chinese Academy of Sciences [KJCX3-SYW-N2]; Program for New Century Excellent Talents in University [NCET-07-0730]; European Commission [CN/ASIA-LINK/008(94791)]; European Scienc

Evolution of deformations in medium-mass nuclei

Evolution of quadrupole deformations in sd- and pf-shell nuclei with mass A=18-56 is studied by using deformed Skyrme Hartree-Fock model with pairing correlations. We point out that the quadrupole deformations of the nuclei with the isospin T=0 and T=1 show strong mass number dependence as a clear manifestation of dynamical evolution of deformation in nuclear many-body systems. The competition between the deformation driving particle-vibration coupling and the closed-shell structure is shown in a systematic study of the ratios between the proton and neutron deformations in nuclei with T=|T{sub z}|=1. Calculated quadrupole and hexadecapole deformations are compared with shell model results and available experimental data. A relation between the skin thickness and the intrinsic Q{sub 2} moments is also discussed.

Effect of tensor interaction on deformation and shell structure of medium-heavy and superheavy nuclei

Japanese Ministry of Education, Culture, Sports, Science and Technology [(C (2)) 20 540 277]; National Science Foundation of China [10 975 116]; Program for New Century Excellent Talents in University [NCET-07-0730]; Fundamental Research Funds for the Central Universities [2010 121 011]

Charge exchange spin-dipole excitations in Zr-90 and Pb-208 and the neutron matter equation of state

Charge exchange spin-dipole (SD) excitations in 90 Zr and 208 Pb are studied by using a Skyrme Hartree-Fock + random phase approximation. The calculated spin-dipole strength distributions are compared with experimental data obtained by 90 Zr(p,n) 90 Nb and 90 Zr(n,p) 90 Nb reactions. The model-independent SD sum rule values of various Skyrme interactions are studied in comparison with the experimental values to determine the neutron skin thickness of 90 Zr. The pressure of the neutron matter equation of state and the nuclear matter symmetry energy are discussed in terms of the neutron skin thickness and peak energies of SD strength distributions.

Tensor correlation, pairing interaction, and deformation in Ne isotopes and Ne hypernuclei

We study tensor and pairing effects on the quadruple deformation of neon isotopes based on a deformed Skyrme-Hartree-Fock model with BCS approximation for the pairing channel. We extend the SkyrmeHartree-Fock formalism for the description of single- and d ouble-lambda hypernuclei adopting two different hyperon-nucleon interactions. It is found that the inte rplay of pairing and tensor interactions is crucial to derive the deformations in several neon isotopes. Especi ally, the shapes of 26,30 Ne are studied in details in comparisons with experimentally observed shapes. Furthermore the deformations of the hypernuclei are compared with the corresponding neon isotopic cores in the presence of tensor force. We find the same shapes with somewhat smaller deformations for single Λ-hypernuclei compared with their core deformations. It is also pointed out that the latest version of hyper on interaction, the ESC08b model, having a deeper Λ potential makes smaller deformations for hypernuclei than those of another NSC97f model.

Possible shape coexistence and magnetic dipole transitions in C-17 and Ne-21

Japanese Ministry of Education, Culture, Sports, Science and Technology [C(2) 18540290, 20540277]; National Science Foundation of China [10605018]; New Century Excellent Talents in University [NCET-07-0730]

Beyond-mean-field study of the hyperon impurity effect in hypernuclei with shape coexistence

[Background] The hyperon impurity effect in nuclei has been extensively studied in different mean-field models. Recently, there is a controversy about whether the

Observation of isomeric states in197Bi

\Lambda

KAONIC NUCLEI IN THE SKYRME–HARTREE–FOCK APPROACH

hyperon is more tightly bound in the normal deformed (ND) states than that in the superdeformed (SD) states.[Purpose] This article is aimed to provide a beyond-mean-field study of the low-lying states of hypernuclei with shape coexistence and to shed some light on the controversy.[Method] The models of relativistic mean-field and beyond based on a relativistic point-coupling energy functional are adopted to study the low-lying states of both