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中子星物质中的K介子凝聚

高能物理与核物理 2003年第2期27卷 113-117页

作者：郭华刘波李希国陈晏军兰州重离子加速器国家实验室原子核理论中心兰州730000 北京大学技术物理系

用密度相关的相对论平均场理论计算了中子星物质中的K介子凝聚 ,结果表明中子星物质发生K介子凝聚的临界密度约为 2 .75 ρ0 .中子星物质URCA过程发生的临界密度在考虑DB核物质中核子自能动量修正时为 ρρ0≈ 3.16,在不考虑DB核物质中... 详细信息

用密度相关的相对论平均场理论计算了中子星物质中的K介子凝聚 ,结果表明中子星物质发生K介子凝聚的临界密度约为 2 .75 ρ0 .中子星物质URCA过程发生的临界密度在考虑DB核物质中核子自能动量修正时为 ρρ0≈ 3.16,在不考虑DB核物质中核子自能动量修正时为 ρρ0≈ 2 .2 5 ,并进一步计算了密度相关的相对论平均场理论两种参数形式对中子星物质状态方程的影响 .

关键词： K介子凝聚密度相关相对论平均场理论中子星物质

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核介质对介子有效质量的影响

高能物理与核物理 2004年第4期28卷 392-397页

作者：陈晏军郭华北京大学技术物理系教育部重离子物理重点实验室北京100871 兰州重离子加速器国家实验室原子核理论中心兰州730000

在密度相关的相对论平均场近似下 ,研究了核介质密度对σ ,ω ,ρ ,π介子有效质量的影响并与线性Walecka模型、非线性Walecka模型及TW模型的计算相比较 ,结果表明不同模型参数下的介子有效质量的变化不会有太大的差别 .在低密度区域内 ... 详细信息

在密度相关的相对论平均场近似下 ,研究了核介质密度对σ ,ω ,ρ ,π介子有效质量的影响并与线性Walecka模型、非线性Walecka模型及TW模型的计算相比较 ,结果表明不同模型参数下的介子有效质量的变化不会有太大的差别 .在低密度区域内 ,介子有效质量随核物质密度的增大而减小 ,而在密度较高时 ,σ ,π介子的有效质量随核物质密度的增大而增大 ,ω ,ρ介子的有效质量随核物质密度的增大其减小趋于平缓 .不对称系数α对介子有效质量的影响很小 .在TM1参数中σ介子的非线性自相互作用项以及多体耦合项 (σπ) 2 对于π介子有效质量的影响是重要的 .

关键词：核介质有效质量密度相关相对论平均场模型不对称系数多体耦合项介子物理

New Parametrizations for a Model with Nonlinear Derivative Couplings

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Chinese Physics Letters 2014年第7期31卷 55-58页

作者：陈晏军 Department of Physics and Electronic Science Changsha University of Science and Technology Changsha 410114

We propose three parameter sets for the Lagrangian with nonlinear derivative couplings in the relativistic mean field theory. The properties of finite nuclei and nuclear matter are explored. The study shows that a good description of binding energies, charge radii and neutron skin thickness of nuclei is achieved with this Lagrangian. It is also shown that this Lagrangian model leads to a softening of the equation of state and symmetry energy at high densities, and gives a much less repulsive optical potential at high nucleon energies compared to standard relativistic mean field models.

关键词： Couplings

Quasielastic electron scattering in a derivative coupling model with relativistic random phase approximation

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Chinese Physics C 2013年第7期37卷 33-38页

作者：陈晏军 Department of Physics and Electronic Science Changsha University of Science and Technology

We apply the derivative coupling model with ZM and ZM3 parameters to investigate the longitudinal response function in quasielastic electron scattering in the relativistic random phase approximation. The non-spectral method is chosen to describe the nucleon Green＇s function in a finite nucleus. Some remarks have been made in conclusion.

关键词： quasielasic electron scattering derivative coupling model relativistic random phase approximation,relativistic mean field theory

Nuclear matter and neutron star properties with the extendedNambu-Jona-Lasinio model

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Chinese Physics C 2019年第3期43卷 82-90页

作者： Yan-Jun Chen Department of Physics and Electronic Science Changsha University of Science and TechnologyChangshaHunan 410114China Hunan Provincial Key Laboratory of Flexible Electronic Materials Genome Engineering ChangshaHunan 410114China

An extended Nambu-Jona-Lasinio(eNJL) model with nucleons as the degrees of freedom is used to investigate properties of nuclear matter and neutron stars(NSs),including the binding energy and symmetry energy of the nuclear matter, the core-crust transition density, and mass-radius relation of NSs. The fourth-order symmetry energy at saturation density is also investigated. When the bulk properties of nuclear matter at saturation density are used to determine the model parameters, the double solutions of parameters are obtained for a given nuclear incompressibility. It is shown that the isovector-vector interaction has a significant influence on the nuclear matter and NS properties, and the sign of isovector-vector coupling constant is critical in the determination of the trend of the symmetry energy and equation of state. The effects of the other model parameters and symmetry energy slope at saturation density are discussed.

关键词： neutron stars nuclear matter extended Nambu-Jona-Lasinio model symmetry energy

Effects of the Recombination of Nucleons into α-Particles on the R-process in Proto-magnetar Wind

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Chinese Physics Letters 2012年第6期29卷 303-306页

作者： CHEN Yan-Jun YUAN Ye-Fei Department of Physics and Electronic Science Changsha University of Science and TechnologyChangsha 410114 Center for Astrophysics University of Science and Technology of ChinaHefei 230026

We take the recombination of nucleons to α-particles into account in proto-magnetar winds and evaluate its effects on r-process *** proto-magnetar winds are described in the time-independent Newtonian magnetohydrodynamic wind *** is found that stellar rotation and strong magnetic fields significantly affect the properties of the ***,the fact that the recombination of nucleons can enhance the wind entropy by approximately twenty percent and somewhat reduce the expansion timescale indicates that the effects of this recombination on the r-process can not be ignored.

关键词： process rotation Newtonian

Deuteron under strong magnetic fields: Skyrme model study

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Chinese Physics C 2023年第3期47卷 146-153页

作者：陈晏军蒋威 Department of Physics and Electronic Science Changsha University of Science and TechnologyChangsha 410114China Hunan Provincial Key Laboratory of Flexible Electronic Materials Genome Engineering Changsha 410114China

We explore the deuteron under strong magnetic fields in Skyrme *** effects of the derivative dependent sextic term in the Skyrme Lagrangian are investigated,and the rational map approximation is used to de-scribe the *** influences of strong magnetic fields on the electric charge distribution and mass of the deu-teron arediscussed.

关键词： skyrmion strong magnetic fields deuteron

Crust-core transition and dynamical instabilities in neutron stars for model with point-coupling interactions

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Chinese Physics C 2021年第7期45卷 232-239页

作者： Yan-jun Chen Zi-peng Cheng Bin-guang He Department of Physics and Electronic Science Changsha University of Science and TechnologyChangsha 410114China Hunan Provincial Key Laboratory of Flexible Electronic Materials Genome Engineering Changsha 410114China

We explore the effects of the density dependence of symmetry energy on the crust-core phase transition and dynamical instabilities in cold and warm neutron stars in the relativistic mean field(RMF)theory with point-coupling interactions using the Vlasov *** role of neutrino trapping is also *** crust-core transition density and pressure,distillation effect,and cluster size and growth rates are *** present work shows that the slope of symmetry energy at saturation,temperature,and neutrino trapping have non-negligible effects.

关键词： crust-core transition dynamical instabilities point-coupling interactions symmetry energy

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电机密封球轴承密封性能分析

轴承 2024年

作者：晏军王呈豪邓四二河南科技大学机电工程学院中国航发四川燃气涡轮研究院

针对一种电机用脂润滑深沟球轴承为对象，建立流热耦合模型，研究轴承的密封性能。在滚动轴承动力学理论以及流体力学理论的基础上，建立脂润滑密封深沟球轴承动力学微分方程组，求解多相流模型并对轴承几何参数影响下的密封特性进行了... 详细信息

针对一种电机用脂润滑深沟球轴承为对象，建立流热耦合模型，研究轴承的密封性能。在滚动轴承动力学理论以及流体力学理论的基础上，建立脂润滑密封深沟球轴承动力学微分方程组，求解多相流模型并对轴承几何参数影响下的密封特性进行了研究。研究结果表明：(1)轴承几何参数对润滑脂泄漏质量流率影响显著，润滑脂泄漏速率随着轴承保持架引导间隙增大而减小，随着轴承径向游隙和保持架兜孔直径的增大而减小，而增大轴承外沟曲率半径，润滑脂泄漏速率呈现先减小后增大的趋势。(2)轴承润滑脂填脂率对润滑脂泄漏速率影响显著，填脂率过大会使润滑脂与滚动体搅动摩擦生热增加，导致泄漏加快；填脂率过少容易导致滚动体接触区域润滑不良；对于本文研究的轴承，填脂率选用30%时最佳，此时密封寿命最长。

关键词：密封脂润滑深沟球轴承轴承动力学多相流