S. Q. Zhang

Relativistic continuum Hartree Bogoliubov theory for ground-state properties of exotic nuclei

The Relativistic Continuum Hartree-Bogoliubov (RCHB) theory, which properly takes into account the pairing correlation and the coupling to (discretized) continuum via Bogoliubov transformation in a microscopic and self-consistent way, has been reviewed together with its new interpretation of the halo phenomena observed in light nuclei as the scattering of particle pairs into the continuum, the prediction of the exotic phenomena - giant halos in nuclei near neutron drip line, the reproduction of interaction cross sections and charge-changing cross sections in light exotic nuclei in combination with the Glauber theory, better restoration of pseudo-spin symmetry in exotic nuclei, predictions of exotic phenomena in hypernuclei, and new magic numbers in superheavy nuclei, etc. Recent investigations on new effective interactions, the density dependence of the interaction strengths, the RMF theory on the Woods-Saxon basis, the single-particle resonant states, and the resonant BCS (rBCS) method for the pairing correlation, etc. are also presented in some detail. (c) 2005 Elsevier B.V. All rights reserved.

Possible existence of multiple chiral doublets in (106)Rh

Adiabatic and configuration-fixed constraint triaxial relativistic mean field (RMF) approaches are developed for the first time and a new phenomenon, the existence of multi chiral-doublets (M

Magic numbers for superheavy nuclei in relativistic continuum Hartree–Bogoliubov theory

\chi

Chiral bands for a quasi-proton and quasi-neutron coupled with a triaxial rotor

D), i.e., more than one pairs of chiral doublets bands in one single nucleus, is suggested for nuclei in A~100 region, typically for

Open problems in understanding the nuclear chirality

^{106}

Description of chiral doublets in A similar to 130 nuclei and the possible chiral doublets in A similar to 100 nuclei

Rh, based on the triaxial deformations together with their corresponding proton and neutron configurations.

Evidence for Multiple Chiral Doublet Bands in 133Ce

The magic proton and neutron numbers are searched in the superheavy region with proton number Z = 100-140 and neutron number N = (Z + 30)-(2Z + 32) in the relativistic continuum Hartree-Bogoliubov (RCHB) theory with effective interactions NL1, NL3, NLSH, TM1, TW99, DD-ME], PK1, and PK1R. Based on the two-nucleon separation energies S-2p and S-2n, the two-nucleon gaps delta(2p) and delta(2n), the shell correction energies E-shell(p) and E-shell(n), the pairing energies E-pair(p) and E-pair(n). and the pairing gaps Delta(p) and Delta(n) Z 120, 132, and 138 and N = 172, 184, 198, 228, 238, and 258 are suggested to be the magic numbers within the present approach. The of-decay half-lives are also discussed. In addition, the potential energy surfaces of possible doubly magic nuclei are obtained by using the deformation-constrained relativistic mean field (RMF) theory, and the shell effects stabilizing nuclei are investigated. (c) 2005 Elsevier B.V. All rights reserved.

Novel structure for magnetic rotation bands in 60Ni

A particle rotor model (PRM) with a quasi-proton and a quasi-neutron coupled with a triaxial rotor is developed and applied to study chiral doublet bands with configurations of an h{sub 11/2} proton and an h{sub 11/2} quasi-neutron. With pairing treated by the BCS approximation, the present quasiparticle PRM is aimed at simulating one proton and many neutron holes coupled with a triaxial rotor. After a detailed analysis of the angular momentum orientations, energy separation between the partner bands, and behavior of electromagnetic transitions, for the first time we find aplanar rotation or equivalently chiral geometry beyond the usual one proton and one neutron hole coupled with a triaxial rotor.

Chirality in odd-A nucleus 135Nd in particle rotor model

Open problems in the interpretation of the observed pair of near-degenerate ΔI = 1 bands with the same parity as the chiral doublet bands are discussed. The ambiguities for the existing fingerprints of the chirality in atomic nuclei and problems in existing theory are discussed, including the description of quantum tunneling in the mean field approximation as well as the deformation, core polarization and configuration of the particle rotor model (PRM). Future developments of the theoretical approach are anticipated.

The first candidate for chiral nuclei in the A~80 mass region: 80Br

The chiral doublets,for nuclei in Asimilar to100 and 130 regions have been studied with the particle-rotor model. The experimental spectra of chiral partner bands for four N=75 isotones in Asimilar to130 region have been well reproduced by the calculation with the configuration pih(11/2)circle timesnuh(11/2)(-1). The possible chiral doublets in Asimilar to100 region have been predicted by the particle-rotor model with the configuration pig(9/2)circle timesnug(9/2)(-1) based on the analysis of the spectra, the omega-I relation, the B(M1) and B(E2) transition probabilities, and the structure of the wave functions. The possible chiral doublets for nuclei with asymmetric particle and hole configurations are also discussed.