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Chinese Physics C 2018年第11期42卷 78-84页

作者： Xiao-Bao Wang Guo-Xiang Dong Hua-Lei Wang Cen-Xi Yuan Yong-Jing Chen Ya Tu School of Science Huzhou UniversityHuzhou 313000China School of Physics and Engineering Zhengzhou UniversityZhengzhou 450001China Sino-Prench Institute of Nuclear Engineering and Technology Sun Yat-Sen UniversityZhuhai 519082China Key Laboratory of Science and Technology on Nuclear Data China Institute of Atomic EnergyBeijing 102413China School of Physics Science and Technology Shenyang Normal UniversityShenyang 110034China

We investigate many-body correlations caused by two- and three-body （2-, 3bd） forces. shell-model effective interactions derived from ab initio methods （coupled-cluster method, no-core shell model） are adopted. Vlow-k potentials, based on many-body perturbation theory, are also tested, especially for their cut-off dependence. We compare the central, tensor and spin-orbit interactions from microscopic theory to the fitted interactions. After the inclusion of the three-body force, the matrix elements become fairly close to those fitted directly to experimental data. Calculations of neutron-rich oxygen isotopes are performed, to clarify the effects of 3bd forces, tensor, and spin-orbit interactions on the nuclear binding and excitation energies. We find that the 3bd force can influence the binding energies greatly, which also determines the drip line position, while its effect on excitation energies is not very pronounced. The spin-orbit force, which is part of the 2bd force, can affect the shell structure explicitly, at least for neutron-rich systems.

关键词： shell model effective interactions tensor force three-body force

Phonon Dispersion and Thermodynamics Properties of CaF_2 via shell model Molecular Dynamics Simulations

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Communications in Theoretical Physics 2009年第5期51卷 904-908页

作者： CHENG Yan HU Cui-E ZENG Zhao-Yi GONG Min GOU Qing-Quan College of Physical Science and Technology Sichuan University Chengdu 610064 China Institute of Atomic and Molecular Physics Sichuan University Chengdu 610065 China

The phonon and thermodynamics properties of face-centered cubic CaF2 at high pressure and high temperature are investigated by using the shell model interatomic pair potential within General Utility Lattice Program （GULP）. The phonon dispersion curves and the corresponding density of state （PDOS） in this work are consistent with the experimental data and other theoretical results. The transverse optical （TO） and longitudinal optical （LO） mode splitting as well as heat capacity at constant volume Cv and entropy S versus pressure and temperature are also obtained.

关键词： shell model molecular dynamics phonon dispersion thermodynamic property CaF2

Elastic Constants of Superconducting MgB2 from Molecular Dynamics Simulations with shell model

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Communications in Theoretical Physics 2005年第5X期44卷 936-940页

作者： GUO Yun-Dong CHEN Xiang-Rong YANG Xiang-Dong GOU Qing-Quan Institute of Atomic and Molecular Physics Sichuan University Chengdu 610065 China Department of Physics Neijiang Teacher's College Neijiang 641112 China International Centre for Materials Physics the Chinese Academy of Sciences Shenyang 110016 China

The elastic constants of superconducting MgB2 are calculated using a molecular dynamics method (MD)with shell model. The lattice parameters, five independent elastic constants, equations of state (EOS), Debye temperature, and bulk modulus of MgB2 are obtained. Meanwhile, the dependence of the bulk modulus B, the lattice parameters a and c, and the unit cell volume V on the applied pressure are presented. It is demonstrated that the method introduced here can well reproduce the experimental results with a reasonable accuracy.

关键词： MgB2 elastic constants shell model molecular dynamics

Anomalous scaling in a non-Gaussian random shell model for passive scalars

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Chinese Physics B 2007年第10期16卷 2848-2854页

作者：赵英奎陈式刚王光瑞 Graduate School of China Academy of Engineering Physics Beijing 100088 China Center for Nonlinear Studies Institute of Applied Physics and Computational Mathematics Beijing 100088 China

In this paper, we have introduced a shell-model of Kraichnan＇s passive scalar problem. Different from the original problem, the prescribed random velocity field is non-Gaussian and σ correlated in time, and its introduction is inspired by She and Levveque （Phys. Rev. Lett. 72, 336 （1994））. For comparison, we also give the passive scalar advected by the Gaussian random velocity field. The anomalous scaling exponents H（p） of passive scalar advected by these two kinds of random velocities above are determined for structure function with values of p up to 15 by Monte Carlo simulations of the random shell model, with Gear methods used to solve the stochastic differential equations. We find that the H（p） advected by the non-Gaussian random velocity is not more anomalous than that advected by the Gaussian random velocity. Whether the advecting velocity is non-Gaussian or Gaussian, similar scaling exponents of passive scalar are obtained with the same molecular diffusivity.

关键词： scaling shell model She and Leveque (SL) model non-Gaussian passive scalar

The Gamow shell model with realistic interactions:a theoretical framework for ab initio nuclear structure at drip-lines

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Communications in Theoretical Physics 2022年第9期74卷 284-298页

作者： Nicolas Michel Jianguo Li Furong Xu CAS Key Laboratory of High Precision Nuclear Spectroscopy Institute of Modern PhysicsChinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijingChina School of Physics and State Key Laboratory of Nuclear Physics and TechnologyPeking UniversityBeijing 100871China

Ab initio approaches are among the most advanced models to solve the nuclear many-body *** particular,the no-core-shell model and many-body perturbation theory have been recently extended to the Gamow shell model framework,where the harmonic oscillator basis is replaced by a basis bearing bound,resonance and scattering states,*** Berggren *** continuum coupling is included at basis level and as configuration mixing takes care of internucleon correlations,halo and resonance nuclei can be properly described with the Gamow shell *** development of the no-core Gamow shell model and the introduction of the■-box method in the Gamow shell model,as well as their first ab initio applications,will be reviewed in this *** compared to models using harmonic oscillator bases will be shortly *** current power and limitations of ab initio Gamow shell model will also be discussed,as well as its potential for future applications.

关键词： binding energy lifetimes nucleon-nucleon interactions shell model continuum coupling

Cause Analysis and Countermeasures of Flight Delay Based on shell model

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校园英语 2020年第1期 254-255页

作者： Yu xiao Cheng Xiao-kang Civil Aviation Flight University of China

As an important mode of modern transportation, transportation aviation is favored by more and more passengers. However,the main factors causing flight delays are analyzed from four aspects. And combined with the characteristics of China's transportation aviation operation, the paper puts forward the countermeasures of flight delay, aiming at providing constructive suggestions to alleviate flight delay.

关键词： flight delay shell model cause of formation countermeasures

Prediction of Radioactive Half-Lives and Atomic Nucleus Dimensions in a Concentric shell model or Flocon model

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Journal of Modern Physics 2022年第8期13卷 1216-1251页

作者： Marc Mignonat Société d’Astronomie des Pyrénées Occidentales Pau France

Considering only the wave aspect, we determine the energy of a bond between 2 nucleons;this quantified energy is associated with a standing wave. Then, starting from the mass loss corresponding to this energy, we determine the number of bonds in this nucleus. The mass defect value for a link is used to determine a specific length at that link. Fixing a precise distance between nucleons makes it possible to determine a geometry of the nucleus and its dimensions. It makes it possible to understand when this bond is stronger than the electrostatic force and allows deducing a shell model built in a precise order. The calculation on the mass defect will also make it possible to determine that one or more nucleons concerned by the radioactivity will be bound by a single bond to the rest of the nucleus or, on the contrary, bound by several bonds which induce short 1/2 lives or, on the contrary, very long. The analysis of the bonds on H, He and C make it possible to write formulae which are then applied to the nuclei to find the radioactive 1/2 lives. To find by equations the radioactive 1/2 lives does not call into question the standard model since it concerns only the defect of mass of the nuclei with energies that are not used to find the main particles of the standard model. This model, which favours a geometric approach to the detriment of a mathematical approach based on differential equations, can lead to theoretical questions about the possibility of interpreting the structure of the nucleus in a more undulatory way. It is possible to explain radioactivity in a more deterministic way.

关键词： ½ Radioactive Lives Atomic Nucleus Dimensions shell model

β-decay studies approaching the N=20 island of inversion with a new shell-model Hamiltonian

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Science China(Physics,Mechanics & Astronomy) 2017年第8期60卷 15-20页

作者： WeiGuang Jiang BaiShan Hu FuRong Xu Rui Han Hui Hua School of Physics and State Key Laboratory of Nuclear Physics and Technology Peking University

β-decay properties of N=18-22,Z=10-14 nuclei are analyzed with a new shell-model Hamiltonian using the Gogny densitydependent *** Gogny force which has been widely and successfully used in mean-field theory can provide reasonable two-body matrix elements for cross-shell *** log f t values andβ-decay level schemes are systematically studied using the D1S-Gogny interaction and compared with the SDPF-M results and experimental *** is shown that the new Hamiltonian provides reliable results forβ-decay along with subtle level schemes for this ***-model calculations with Gogny interaction can lead to a successful description of nuclei in and around the N=20 island of inversion and supplements experiment where sufficient data are not available.

关键词： island of inversion β decay shell model Gogny interaction

SD-PAIR shell model FOR EVEN-EVEN SYSTEMS

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SD-PAIR SHELL MODEL FOR EVEN-EVEN SYSTEMS

shell-model study on properties of proton dripline nuclides with Z,N=30-50 including uncertainty analysis

第十三届全国核结构研讨会暨第九次全国“核结构与量子力学”专题讨论会

作者： Jerry P.Drayer Department of Physics and Astronomy Louisiana State UniversityBaton RougeLA 70803USA

A nucleon-pair shell model was proposed in 1993 by *** to the success of the interacting boson model,the full shell model space in the nucleon-pair shell model was truncated to SD-pair subspace, called SD-pair shell *** this model,the ex- perimental spectra in medium-weight and heavy nuclei, limiting cases in the interacting boson model,phase transitions,*** be reproduced approximately.

关键词： shell model SD-pair Collectivity IBM

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Chinese Physics C 2022年第8期46卷 196-210页

作者： Bo-Shuai Cai Guang-Shang Chen Cen-Xi Yuan Jian-Jun He Sino-French Institute of Nuclear Engineering and Technology Sun Yat-Sen UniversityZhuhai 519082China Key Laboratory of Beam Technology and Materials Modification of Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China Beijing Radiation Center Beijing 100875China

The binding and proton separation energies of nuclides with Z,N=30-50 are investigated based on the shell model,with an uncertainty analysis via statistical *** formulas are used to obtain the binding and proton separation energies according to shell-model *** non-parametric bootstrap method is applied to establish an uncertainty decomposition and recomposition ***,this is used to estimate the stability of proton(s) emission for each *** formulas for calculating the binding energies with a systematic uncertainty of~0.3 Me V are proposed,and a reliable extrapolation ability is *** binding energy formulas deduce similar forms for their respective S_(p) and S_(2 p) energies,which predict the extension of the nuclear boundary of this region.A good description of the binding and proton separation energies is *** one-and twoproton separation energies and partial half-lives of proton emission are predicted,thus revealing a new ***,there are 30 unstable nuclides predicted to be bound against proton(s)-*** nuclear properties will be useful in nuclear astrophysics.

关键词： shell model proton dripline uncertainty analysis