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It is known that pseudospin symmetry plays a crucial role in formation of many physical phenomena. By combining the relativistic mean field theory with the complex momentum representation method, the pseudospin symmetry in the single particle resonant states in the deformed nucleus 1 5 4 Dy is investigated through the energy and width splittings, the quadrupole deformation parameter, the radial density distributions and occupation probabilities of the pseudospin doublets. Near the continuum threshold, the pseudospin symmetry is well reserved in both bound and resonant states. The energy and width splittings of pseudospin doublets in resonant states exhibit correlations with the deformation and quantum numbers. The good pseudospin symmetry is expected with lower pseudo-orbital angular momentum projection Λ ̃ and the main quantum number N. In general, an increase in deformation tends to weaken the quality of the pseudospin symmetry. The understanding of the evolution of the pseudospin doublets in the resonant states has been deepened by studying the pseudospin symmetry in the deformed nuclei. [ABSTRACT FROM AUTHOR]

The location of the neutron drip line, currently known for only the lightest elements, remains a fundamental question in nuclear physics. Its description is a challenge for microscopic nuclear energy density functionals, as it must take into account in a realistic way not only the nuclear potential, but also pairing correlations, deformation effects and coupling to the continuum. The recently developed deformed relativistic Hartree–Bogoliubov theory in continuum (DRHBc) includes all three aforementioned effects in the description of nuclei throughout the nuclear chart. Here, the DRHBc with the successful density functional PC-PK1 is used to investigate whether and how deformation influences the prediction for the neutron drip-line location for even–even nuclei with 8 ≤ Z ≤ 2 0 , where many isotopes are predicted deformed. The results are compared with those based on the spherical relativistic continuum Hartree–Bogoliubov (RCHB) theory and discussed in terms of shape evolution and the variational principle. It is found that the Ne and Ar drip-line nuclei are different after the deformation effect is included. The direction of the change is not necessarily towards an extended drip line, but rather depends on the evolution of the degree of deformation towards the drip line. Deformation effects as well as pairing and continuum effects treated in a consistent way can affect critically the theoretical description of the neutron drip-line location. [ABSTRACT FROM AUTHOR]

Magnetic dipole moments of the ground- and excited-states below 600 keV in 1 8 3 , 1 8 5 W, 1 8 5 , 1 8 7 Re and 1 8 7 , 1 8 9 Os nuclei have been systematically studied in the framework of a microscopic Quasiparticle Phonon Nuclear Model (QPNM) including an axially symmetric Wood–Saxon potential as a mean field and the residual spin–spin interaction. The obtained results of the magnetic moment, intrinsic g K factor and the effective spin gyromagnetic factor have been compared with the available experimental data and also with the calculations based on different approaches. It has been demonstrated that the QPNM reproduces reasonably well the recent experimental value of the ground-state magnetic moment and satisfactorily describes the measured magnetic moment of low-lying states below 600 keV in these nuclei. [ABSTRACT FROM AUTHOR]

We investigated the orientation behavior of the interaction potential between highly-deformed oblate 2 8 Si nuclei and its influences on the fusion process. The deformed–deformed potential is calculated using the double-folding model based on the realistic M3Y-Reid nucleon–nucleon interaction. We found that the Coulomb barrier parameters and the sub-barrier fusion data strongly depend on the polar orientation angles of the involved deformed nuclei, with a rather less dependence on the azimuthal angles. For interacting oblate nuclei, the elongated configuration corresponding to the lowest Coulomb barrier is obtained at orthogonal polar orientations, while the hexadecapole deformation determines the compact configuration obtained at nonzero polar orientations. The orientation behavior of the Coulomb barrier radius (height and curvature) consistently follow (inversely reflex) the orientation variation of the sum of the half-density radii of the two deformed nuclei, along their centers-of-mass separation vector. The deformations of the colliding nuclei increase their fusion cross-section at sub- and around-barrier energies. The calculations based on the parabolic barrier approximation overestimate the sub-barrier cross-section. The coupled channels calculations with couplings up to the 2 + and 4 + excitation states of 2 8 Si nuclei are needed to reproduce the 2 8 Si + 2 8 Si fusion cross-section, and the corresponding logarithmic slope and barrier distribution, over the full energy region. [ABSTRACT FROM AUTHOR]

We study nuclear structure properties for various isotopes of Ytterbium (Yb), Hafnium(Hf), Tungsten(W), Osmium(Os), Platinum(Pt) and Mercury(Hg) in = 70-80 drip-line region starting from to within the formalism of relativistic mean field (RMF) theory. The pairing correlation is taken care by using BCS approach. We compared our results with finite range droplet model(FRDM) and experimental data and found that the calculated results are in good agreement. Neutron shell closure is obtained at and in this region. We have also studied probable decay mechanisms of these elements. [ABSTRACT FROM AUTHOR]

In this paper we report the different orientations effect on the high-density matter in deformed UU collisions at CSR energy. ART model is used in our analysis. We have tested and developed two measurements, the forward neutron multiplicity and nuclear stopping, which permit us to select the special UU collisions with extended high-density phase. [ABSTRACT FROM AUTHOR]

The Coulomb and nuclear heavy ion (HI) potentials are derived for an interacting pair of deformed nuclei assuming sharp surface model for each nucleus. The orientation and separation dependences of the Coulomb and nuclear interactions are studied. It is assumed 238U + 238U as an example, and the effect of quadrupole term is investigated. For the nuclear potential part based on M3Y nucleon–nucleon interaction, the sharp surface model shows much difference compared with the more accurate frequently used multipole expansion method while the success of this model in calculating the Coulomb potential between this deformed pair of nuclei exists in the physically important surface region. [ABSTRACT FROM AUTHOR]