检索结果-南通市图书馆

Structure of high spin state in proton-rich ^(74,76,78)Kr isotopes:A projected shell model description

在线全文

学校读者我要写书评

暂无评论

Science China(Physics,Mechanics & Astronomy) 2015年第1期58卷 32-37页

作者： LIU YanXin yu shaoying SHEN CaiWan School of Science Huzhou Teachers College

The N≈Z nuclei in the mass A^80 region has been researched because of an abundance of nuclear structure *** projected shell model(PSM)was adopted to investigate the structure of high spin state in proton-rich 74,76,78Kr isotopes including yrast spectra,moment of inertia,electric quadrupole transitions and the behavior of single *** calculated results are in good agreement with available data and the shape coexistence in low-spin is also discussed.

关键词： projected shell model high spin state moment of inertia electric quadrupole transition

On the structure of isomeric state in neutron-rich 108Zr: A projected shell model analysis

在线全文

学校读者我要写书评

暂无评论

Science China(Physics,Mechanics & Astronomy) 2015年第11期58卷 92-98页

作者： LIU YanXin yu shaoying SUN Yang School of Science Huzhou University Department of Physics and Astronomy Shanghai Jiao Tong University IFSA Collaborative Innovation Center Shanghai Jiao Tong University State Key Laboratory of Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences

Inspired by the recent experimental identification of the new isomer with a half-life of （620±150） ns in the very neutron-rich nucleus 180SZr, we apply the projected shell model with axially-deformed bases to discuss possible shapes near the ground state and the nature of the isomer. The structure of the new isomer is investigated by restricting the calculation to prolate and oblate shapes. It is shown that the isomer can be understood as a K-isomer. Meanwhile, the calculation predicts more low-lying high-K configurations, which may be confirmed by future experiments,

关键词： K isomer shape isomer prolate shape oblate shape projected shell model

An investigation of ab initio shell-model interactions derived by no-core shell model

在线全文

学校读者我要写书评

暂无评论

Science China(Physics,Mechanics & Astronomy) 2016年第9期59卷 52-58页

作者： XiaoBao Wang GuoXiang Dong QingFeng Li CaiWan Shen shaoying yu School of Science Huzhou University

The microscopic shell-model effective interactions are mainly based on the many-body perturbation theory （MBPT）, the first work of which can be traced to Brown and Kuo＇s first attempt in 1966, derived from the Hamada-Johnstou nucleon-nucleon potential. However, the convergence of the MBPT is still unclear. On the other hand, ab initio theories, such as Green＇s function Monte Carlo （GFMC）, no-core shell model （NCSM）, and coupled-cluster theory with single and double excitations （CCSD）, have made many progress in recent years. However, due to the increasing demanding of computing resources, these ab initio applications are usually limited to nuclei with mass up to A = 16. Recently, people have realized the ab initio construction of valence-space effective interactions, which is obtained through a second-time renormalization, or to be more exactly, projecting the full-many- body Hamiltonian into core, one-body, and two-body cluster parts. In this paper, we present the investigation of such ab initio shell-model interactions, by the recent derived sd-shell effective interactions based on effective J-matrix Inverse Scattering Potential （JISP） and chiral effective-field theory （EFT） through NCSM. In this work, we have seen the similarity between the ab initio shell- model interactions and the interactions obtained by MBPT or by empirical fitting. Without the inclusion of three-body （3-bd） force, the ab initio shell-model interactions still share similar defects with the microscopic interactions by MBPT, i.e., T = 1 channel is more attractive while T = 0 channel is more repulsive than empirical interactions. The progress to include more many-body correlations and 3-bd force is still badly needed, to see whether such efforts of ab initio shell-model interactions can reach similar precision as the interactions fitted to experimental data.

关键词： shell model effective interactions ab initio methods

Rotational structure of the odd-proton nuclide ^(171)Tm:A projected shell model study

在线全文

学校读者我要写书评

暂无评论

Science China(Physics,Mechanics & Astronomy) 2015年第5期58卷 76-81页

作者： LIU YanXin CHEN FangQi yu shaoying SUN Yang School of Science Huzhou University China Institute of Atomic Energy Department of Physics and Astronomy Shanghai Jiao Tong University

Deformed odd-mass nuclei are ideal examples where the interplay between single-particle and collective degrees of freedom can be studied. Inspired by the recent experimental high-spin data in the odd-proton nuclide 171 Tm, we perform projected shell model(PSM) calculations to investigate structure of the ground band and other bands based on isomeric states. In addi- tion to the usual quadrupole-quadrupole force in the Hamiltonian, we employ the hexadecapole-hexadecapole(HH) interac- tion, in a self-consistent way with the hexadecapole deformation of the deformed basis. It is found that the known experi- mental data can be well described by the PSM calculation. The effect of the HH force on the quasiparticle isomeric states is discussed.

关键词： rotational band isomeric state hexadecapole-hexadecapole interaction projected shell model

Collective properties of neon isotopes investigated by projected shell model

在线全文

学校读者我要写书评

暂无评论

Chinese Science Bulletin 2014年第29期59卷 3847-3852页

作者： Guoxiang Dong Xiaobao Wang Furong Xu shaoying yu State Key Laboratory of Nuclear Physics and Technology School of PhysicsPeking University Department of Physics University of Jyvskyl40014 JyvskylFinland School of Science Huzhou Teachers College

Collective phenomenon in neon isotopes is an interesting ***,even the ground-state deformations cannot be well described by ***,QJ Zhi and ZZ Ren[Phys Lett B 638:166(2006)]have suggested an improved Nilsson potential,which can give a suitable description of ground-state properties in magnesium *** order to test the description of neon isotopes located around the‘‘island of inversion’’,we have used this potential to provide the deformed basis for the projectedshell-model *** low-lying spectra and transition properties of neon isotopes can be reproduced *** gyromagnetic factors of neon isotopes have also been *** structures of excited states along the yrast line are studied in the language of band diagrams.

关键词：氖同位素投影壳模型基态性质集体霓虹灯物理学尼尔森激发态

Projected total energy surface description for axial shape asymmetry in ^(172)W

在线全文

学校读者我要写书评

暂无评论

Science China(Physics,Mechanics & Astronomy) 2014年第11期57卷 2054-2059页

作者： TU Ya CHEN YongShou GAO ZaoChun yu shaoying LIU Ling College of Physics Science and Technology ShenYang Normal University China Institute of Atomic Energy School of Science Huzhou Teachers College

The projected total energy surface(PTES)approach has been developed based on the triaxial projected shell model(TPSM)hybridized with the macroscopic–microscopic *** total energy of an atomic nucleus is decomposed into macroscopic,microscopic and rotational *** macroscopic and microscopic components are described with the liquid drop model and Strutinsky method,respectively,and the rotational energy is given by the TPSM,the term beyond the mean *** test theory,the PTES calculations have been carried out for the yrast states of the well deformed rare earth nucleus172W,and the theoretical results are in good agreement with the experimental *** using the equilibrium quardrupole deformations(ε2andγ)determined by the PTES,the calculation of the transition quardrupole moment(Qt)in function of spin also reproduces the experimental data.A comparison between the PTES and TRS methods has been made for theoretical and application uses.

关键词： triaxial nucleus deformed rotational projected microscopic asymmetry macroscopic pairing nuclei

Energy Optimization of the Fin/Rudder Roll Stabilization System Based on the Multi-objective Genetic Algorithm （MOGA）

在线全文

学校读者我要写书评

暂无评论

Journal of Marine Science and Application 2015年第2期14卷 202-207页

作者： Lijun yu shaoying Liu Fanming Liu Hui Wang College of Automation Harbin Engineering University Harbin 150001 China

Energy optimization is one of the key problems for ship roll reduction systems in the last decade. According to the nonlinear characteristics of ship motion, the four degrees of freedom nonlinear model of Fin/Rudder roll stabilization can be established. This paper analyzes energy consumption caused by overcoming the resistance and the yaw, which is added to the fin/rudder roll stabilization system as new performance index. In order to achieve the purpose of the roll reduction, ship course keeping and energy optimization, the self-tuning PID controller based on the multi-objective genetic algorithm （MOGA） method is used to optimize performance index. In addition, random weight coefficient is adopted to build a multi-objective genetic algorithm optimization model. The objective function is improved so that the objective function can be normalized to a constant level. Simulation results showed that the control method based on MOGA, compared with the traditional control method, not only improves the efficiency of roll stabilization and yaw control precision, but also optimizes the energy of the system. The proposed methodology can get a better performance at different sea states.

关键词： ship motion energy optimization ship roll reduction performance index self-tuning PID multi-objective geneticalgorithm (MOGA) roll stabilization fin/rudder roll stabilization yaw control precision