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We study the relationship between the properties of the isovector giant dipole resonance of finite nuclei and the symmetry energy in the framework of the relativistic mean field theory with six different parameter sets of nonlinear effective Lagrangian. A strong linear correlation of excited energies of the dipole resonance in finite nuclei and symmetry energy at and below the saturation density is found. This linear correlation leads to the symmetry energy at the saturation density at the interval 33.0MeV ≤ S(ρo) ≤37.0MeV. The comparison to the present experimental data in the soft dipole mode of 132Sn constrains approximately the symmetry energy at p = 0.1 fm−3 at the interval 21.2 MeV ~ 22.5 MeV. It is proposed that a precise measurement of the soft dipole mode in neutron rich nuclei could set up an important constraint on the equation of state for asymmetric nuclear matter.

A relativistic mean field model is used to study the ground-state properties of neutron-rich nuclei in Ca isotopes. An additional isoscalar and isovector nonlinear coupling has been introduced in the relativistic mean field model, which could soften the symmetry energy, while keep the agreement with the experimental data. The sensitivity of proton and neutron density distributions and single particle states in Ca isotopes to the additional isoscalar–isovector nonlinear coupling term is investigated. We found that the binding energies, the density distributions of single particle levels are strongly correlated with the density dependence of the symmetric energy in nuclear matter.

The axially deformed relativistic mean field theory is applied to study the isotope shift of charge distributions of odd-Z Pr isotope chain. The nuclear structure associated with the shell and the isotope effect is investigated. The mechanism of the kink in the isotope shift at the neutron magic number N = 82 is revealed to be dependent on the neutron energy level structure at the Fermi energy, demonstrating that the spin–orbit coupling interaction and p–n attraction are well described by the relativistic mean field theory.

The macroscopic deformed potential energy for super-heavy elements Z = 120 is determined within a generalized liquid drop model (GLDM). The shell correction is calculated with the Strutinsky method and the microscopic single particle energies are derived from the shell model in an axially deformed Woods–Saxon potential with the same quasi-molecular shape. The total potential energy of a nucleus is calculated by the macro-microscopic method as the summation of the liquid-drop energy and the Strutinsky shell correction. The theory is adopted to describe the deformed potential energies in a set of cold reactions. The neck in the quasi-molecular shape is responsible to the deep valley of the fusion barrier due to shell corrections. In the cold fusion path, the double-hump fusion barrier is predicted by the shell correction and complete fusion events may occur. The results show that some of projectile–target combinations in the entrance channel, such as 50Ca+252Fm→ 302120* and 58Fe+244Pu→ 302120*, favour the fusion reaction, which can be considered as candidates for the synthesis of super heavy nuclei Z = 120 and the former might be the best cold fusion reaction to produce the nucleus 302120 among them.

We employ a direct capture method to study the influence of D-state in 4He on S factor for the 2H(d,γ)4He reaction, in which the D-state component of the colliding deuterons and D-state component in 4He ground state are considered. The parameters of Woods–Saxon (WS) potentials are obtained by reproducing the binding energy of d–d (i.e. 2H–2H) system, and d–d elastic scattering phase shifts calculated by the resonating group method. The theoretical results are in good agreement with the experimental data at Ec.m.

The total reaction cross sections (TRCSs) of 29S+28Si have been measured at intermediate energies. An obvious enhancement in TRCS of 29S is observed as compared with its neighbouring nuclei. The TRCSs of 29S+28Si are calculated with the modified Glauber theory in the optical limit and few-body approaches. The different factor d as a possible measure of halo appearance is deduced from the experimental and theoretical data. It is well accepted that 27P is a proton halo nucleus. Although not as anomalous as 27P, the different factor d of 29S is obviously larger than that of its neighbouring isotones of N = 13. This result indicates that a moderate proton halo may exist in 29S nucleus. We calculate the total reaction cross sections for 29S with the modified Glauber theory as a function of incident energy and compare the results with those for 27Si which is a core nucleus of 29S. The measured TRCSs of 27Si+28Si can be described to be satisfactory by the modified Glauber theory of the optical limit approach. Although a diffused nuclear density distribution is used, the theories still inadequately predict the experimental TRCSs of 29S+28Si, which further indicates the possibility of proton halo in 29S.

Finite nucleus properties are studied in a relativistic effective interaction approach. Density dependent coupling constants of the meson-nucleon interactions are adopted to incorporate the relativistic Brueckner-Hartree-Fock results in the relativistic mean field (RMF) or relativistic Hartree-Fock (RHF) approach. It is desired to remedy the deficiencies of RMF and RHF without losing the features of the relativistic G matrix and at the same time retain the simplicity. The calculated ground state properties with the density dependent coupling constants are in a good agreement with experiment. The contribution of isovector mesons in RHF is discussed.

The nonlinear relativistic mean field (RMF) theory with a new effective interaction NL3 has been used to investigate the bulk properties of the 12B nucleus. The results obtained in the RMF predict one neutron halo in a 12B excited state. 12B does not show the neutron halo structure if it is in its ground state.

The quasiparticle effect on the nuclear response in the quasielastic electron scattering is studied in a phenomenological quasiparticle model. The quasiparticle Hamiltonian which includes correlations has been introduced through a parameterization of the effective mass m*(r)/m. It is found that the quasiparticle effective mass plays an important role on the nuclear response functions. Though this model could give better agreement with experiments, the discrepancy in the longitudinal response remains to be eliminated.

The isoscalar giant monopole resonance (ISGMR) in nuclei is studied in the framework of a fully consistent relativistic continuum random phase approximation (RCRPA). In this method the contribution of the continuum spectrum to nuclear excitations is treated exactly by the single particle Green's function technique. The negative energy states in the Dirac sea are also included in the single particle Green's function in the no-sea approximation. The single particle Green's function is calculated numerically by a proper product of the regular and irregular solutions of the Dirac equation. The strength distributions in the RCRPA calculations, the inverse energy-weighted sum rule m(-1) and the centroid energy of the ISGMR in Sn-120 and Pb-208 are analysed. Numerical results of the RCRPA are checked with the constrained relativistic mean field model and relativistic random phase approximation with a discretized spectrum in the continuum. Good agreement between them is achieved.

The microscopic relativistic optical potentials in energy region of E < 300MeV have been studied and calculated. An effective Lagrangian density with two adjustable coupling constants (gσ, gω) is chosen by reproducing the bulk properties of nuclear matter in the Dirac-Hartree-Fock (DHF) approximation. It is found that the optical potential calculated in this model is in good agreement with those obtained by phenomenological fitting up to the energy of 300MeV.

A formulation which counts the contributions to the short range nuclear force from both the quark-gluon and quark-pion interactions in the chiral (and the cloudy) bag has been developed. The effective operators are given in terms of the propagators of the quark, gluon and pion fields. The effective potential can be calculated for any anti-symmetric wave functions of six quarks in a cavity. The calculations have been done for DeTar's six-quark states and those N-N states which are constructed using group classification and fractional parentage reduction. The results show that there is a repulsive core whose strength is about several hundreds MeV in the nuclear potential.