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Particle number scale invariant feature of the states around the critical point of the first order nuclear shape phase transition

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Science China(physics,Mechanics & Astronomy) 2009年第10期52卷 1579-1585页

作者： ZHANG Yu HOU ZhanFeng LIU YuXin Department of physics and State Key laboratory of nuclear physics and Technology Peking UniversityBeijing 100871China center of theoretical nuclear physics National Laboratory of Heavy Ion AcceleratorLanzhou 730000China

We study systematically the evolutive behaviors of some energy ratios,E2 transition rate ratios and isomer shift in the nuclear shape phase *** find that the quantities sensitive to the phase transition and independent of free parameter(s) are approximately particle number N scale invariant around the critical point of the first order phase transition,similar to that in the second order phase transition.

关键词： nuclear shape phase transition critical point particle number scaling behavior interacting boson model

Probing proton halo of the exotic nucleus ^(28)S by elastic electron scattering

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Science China(physics,Mechanics & Astronomy) 2004年第1期47卷 42-51页

作者： WANG Zaijun1 & REN Zhongzhou1’2 1. Department of physics, Nanjing University, Nanjing 210008, China 2. center of theoretical nuclear physics, national laboratory of heavy-ion accelerator at Lanzhou, Lanzhou 730000, China Correspondence should be addressed to Ren Zhongzhou (email: zren@*** zren99@***) Received June 16, 2003 Department of physics Nanjing University Nanjing 210008 China center of theoretical nuclear physics National Laboratory of Heavy-Ion Accelerator at Lanzhou Lanzhou 730000 China

Elastic electron scattering on the exotic light nucleus 28S is investigated in the plane wave Born approximation. The variation of the squared form factors of 28S with momentum transfer is compared with that of 32S. It is found that the behavior of the form factors near the second minimum (with a moderate momentum transfer) is sensitive to the alteration of the charge density distribution of halo protons in 28S. This indicates that elastic electron scattering can be a good probe of the structure of proton-halo nuclei.

关键词： elastic electron scattering, cross section, form factor, proton-halo nucleus.

Half-Lives of Proton Emitters With a Deformed Density-Dependent Model

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Chinese physics Letters 2010年第11期27卷 35-38页

作者：钱以斌任中洲倪冬冬圣宗强 Department of Physcis Nanjing University Nanjing 210093 center of theoretical nuclear physics National Laboratory of Heavy-Ion Accelerator Lanzhou 730000 Kavli Institute for theoretical physics China Beijing 100190

Half-lives of proton radioactivity are investigated with a deformed density-dependent model. The single folding potential which is dependent on deformation and orientation is employed to calculate the proton decay width through the deformed potential barrier. In addition, the spectroscopic factor is taken into account in the calculation, which is obtained in the relativistic mean field theory with NL3. The calculated results of semi-spherical nuclei are found to be in good agreement with the experimental data, and the results of well-deformed nuclei are also satisfactory. Moreover, a formula for the spherical proton emission half-life based on the Gamow quantum tunneling theory is presented.

关键词： nuclear physics

Effect of tensor force on dissipation dynamics in time-dependent Hartree-Fock theory

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Science China(physics,Mechanics & Astronomy) 2014年第9期57卷 1618-1622页

作者： DAI GaoFeng GUO Lu ZHAO EnGuang ZHOU ShanGui State Key laboratory of theoretical physics Institute of Theoretical Physics Chinese Academy of Sciences School of physics University of Chinese Academy of Sciences center of theoretical nuclear physics National Laboratory of Heavy Ion Accelerator

The role of tensor force on the collision dynamics of16O+16O is investigated in the framework of a fully three-dimensional timedependent Hartree-Fock *** calculations are performed with modern Skyrme energy functional plus tensor *** attention is given on the analysis of dissipation dynamics in heavy-ion *** energy dissipation is found to decrease as an initial bombarding energy increases in deep-inelastic collisions for all the Skyrme parameter sets studied here because of the competition between the collective motion and the single-particle degrees of *** reveal that the tensor forces may either enhance or reduce the energy dissipation depending on the different parameter *** fusion cross section without tensor force overestimates the experimental value by about 25%,while the calculation with tensor force T11 has good agreement with experimental cross section.

关键词： time-dependent Hartree-Fock tensor force dissipation dynamics

How and When Will a Neutron Star Become a Hyperon Star?

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Chinese physics Letters 2001年第12期18卷 1571-1574页

作者： JIA Huan-Yu SUN Bao-Xi MENG Jie ZHAO En-Guang Department of Technical physics Peking UniversityBeijing 100871 Institute of theoretical physics Chinese Academy of SciencesBeijing 100080 center of theoretical nuclear physics National Laboratory of Heavy Ion AcceleratorLanzhou 730000

In the framework of the extended relativistic mean-field theory with hyperons, the properties of neutron star matter have been investigated. It is found that at a density of four to five times that of nuclear matter saturation density po, a neutron star will become a hyperon star. This transition is strongly influenced by the coupling constants of hyperons to mesons and a different parameter set. For a given parameter set, a minimum transition baryon density exists when the hyperon coupling ratios satisfy xHσ=xHω=xHρ=0.65 or xHσ=xHω=0.62,xHρ=0.7.

关键词： set coupling satisfy

Existence of Two Higher L=0 Bound States of the Dipositroniums

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Chinese physics Letters 1999年第4期16卷 267-268页

作者： BAO Cheng-guang SHI Ting-yun center of theoretical nuclear physics National Laboratory of Heavy IonLanzhou 730000 Department of physics Zhongshan UniversityGuangzhou 510275

Symmetry has imposed very strong constraints on the internal structure of quantum mechanical *** particular,whether a state can access a given outgoing channel is constrained by *** the dipositroniums,the most important channel is the Ps-Ps ***,based on symmetry consideration it was found that only a few excited states are allowed to access the Ps-Ps channel,thereby at least the existence of two higher L=0 bound states(higher than the Ps-Ps threshold)has been affirmed.

关键词： positronium states allowed

Octupole Deformations of Even-Even Rn, Th, and U Nuclei in Relativistic Mean Field Theory

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Communications in theoretical physics 2010年第6期53卷 1145-1148页

作者：王楠孟杰赵恩广 College of physics Shenzhen University School of physics Beijing University center of theoretical nuclear physics National Laboratory of Heavy ion Accelerator Institute of theoretical physics Chinese Academy of Sciences

The octupole deformations and other ground state properties of even-even Rn, Th and U isotopes are investigated systematically within the framework of the reflection asymmetric relativistic mean field （RAS-RMF） model. The calculation results reproduce the binding energies and the quadrupole deformations well. The calculation results indicate these nuclei at ground states evolve from neaxly-spherical （N = 130） shape to quadrupole deformation shape with the increase of the neutron number. It is also found that among the Rn isotopes, only^222,224 Rn axe oetupole deformed and the octupole deformations for them are small. However, more nuclei （N ≌ 134 148） in Th and U isotopes are octupole deformed and the octupole deformations for some of them are significant （｜β3｜- 0.1 or even larger）.

关键词： binding energy nuclear deformation relativistic mean field theory

Benford's Law and β-Decay Half-Lives

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Communications in theoretical physics 2009年第4期51卷 713-716页

作者： NI Dong-Dong WEI Lai REN Zhong-Zhou Department of physics Nanjing University Nanjing 210093 China center of theoretical nuclear physics National Laboratory of Heavy-Ion Accelerator Lanzhou 730000 China

The experimental values of 2059 β-decay half-lives are systematically analyzed and investigated. We have found that they are in satisfactory agreement with Benford＇s law, which states that the frequency of occurrence of each figure, 1-9, as the first significant digit in a surprisingly large number of different data sets follows a logarithmic distribution favoring the smaller ones. Benford＇s logarithmic distribution of β-deeay half-lives can be explained in terms of Neweomb＇s justification of Benford＇s law and empirical exponential law of β-decay half-lives. Moreover, we test the calculated values of 6721 β-decay half-lives with the aid of Benford＇s law. This indicates that Benford＇s law is useful for theoretical physicists to test their methods for calculating β-decay half-lives.

关键词： Benford's law β-decay half-lives

Shell model calculations for the allowed Gamow-Teller β-decays of light nuclei

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Science China(physics,Mechanics & Astronomy) 2014年第6期57卷 1005-1012页

作者： LI HanTao REN ZhongZhou Department of physics and Key laboratory of Modern Acoustics Institute of AcousticsNanjing University Joint center of nuclear Science and Technology Nanjing University center of theoretical nuclear physics National Laboratory of Heavy-Ion Accelerator

The allowed Gamow-Teller β-decay information of Li, Be, B, C, and N isotopes under the flame work of nuclear shell model is calculated herein. theoretical results of Q values, half-lives, excitation energies, log ft values, branching fractions, and β-delayed proton/neutron emission probabilities are tabulated and compared with experimental data. The deviations from the observations are also analyzed. The llBe nucleus is well known for its anomaly ground state Jπ=1/2＋. Thus, we compared the theoretical energy levels with the experimental data and the agreements for low excitation states are consistent. The quenching factor is also evaluated and discussed.

关键词： light nuclei Gamow-Teller β-decay nuclear shell model