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Research on the influence of quadrupole deformation and continuum effects on the exotic properties of 15,17,19B with the complex momentum representation method 被引量:1
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作者 Xue‑Neng Cao Xian‑Xian Zhou +1 位作者 Ming Fu Xin‑Xing Shi 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第2期98-108,共11页
The properties of exotic nuclei are the focus of the present research.Two-neutron halo structures of neutron-rich17,19B were experimentally confirmed.We studied the formation mechanism of halo phenomena in17,19B using... The properties of exotic nuclei are the focus of the present research.Two-neutron halo structures of neutron-rich17,19B were experimentally confirmed.We studied the formation mechanism of halo phenomena in17,19B using the complex momentum representation method applied to deformation and continuum coupling.By examining the evolution of the weakly bound and resonant levels near the Fermi surface,s–d orbital reversals and certain prolate deformations were observed.In addition,by analyzing the evolution of the occupation probabilities and density distributions occupied by valence neutrons,we found that the ground state of15B did not exhibit a halo and the ground states of17B and19B exhibited halos at 0.6≤β2≤0.7 and0.3≤β2≤0.7,respectively.The low-l components in the valence levels that are weakly bound or embedded in the continuous spectrum lead to halo formation. 展开更多
关键词 Quadrupole deformation Resonant states complex momentum representation HALO
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The complex momentum representation approach and its application to low‑lying resonances in 17 O and^(29,31)F
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作者 Si‑Zhe Xu Shi‑Sheng Zhang +1 位作者 Xiao‑Qian Jiang Michael Scott Smith 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第1期43-50,共8页
Approaches for predicting low-lying resonances,uniformly treating bound,and resonant levels have been a long-standing goal in nuclear theory.Accordingly,we explored the viability of the complex momentum representation... Approaches for predicting low-lying resonances,uniformly treating bound,and resonant levels have been a long-standing goal in nuclear theory.Accordingly,we explored the viability of the complex momentum representation(CMR)approach coupled with new potentials.We focus on predicting the energy of the low-lying 2p_(3∕2)resonance in 17 O,which is critical for s-process nucleosynthesis and missing in previous theoretical research.Using a Woods-Saxon potential based on the Koning-Delaroche optical model and constrained by the experimental one-neutron separation energy,we successfully predicted the resonant energy of this level for the first time.Our predictions of the bound levels and 1d_(3∕2)resonance agree well with the measurement results.Additionally,we utilize this approach to study the near-threshold resonances that play a role when forming a two-neutron halo in^(29,31)F.We found that the CMR-based predictions of the bound-level energies and unbound 1f7∕2 level agree well with the results obtained using the scattering phase shift method.Subsequently,we successfully found a solution for the 2p_(3∕2)resonance with energy just above the threshold,which is decisive for halo formation. 展开更多
关键词 Neutron capture Low-lying resonance complex momentum representation Resonance energy
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Properties of Titanium isotopes in complex momentum representation within relativistic mean-field theory 被引量:2
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作者 Tai-Hua Heng Yao-Wu Chu 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2022年第9期93-100,共8页
The self-consistent quadruple potential is deduced within the relativistic mean-field(RMF)framework and substituted into the Hamiltonian,which is calculated using the complex momentum representation(CMR).Considering e... The self-consistent quadruple potential is deduced within the relativistic mean-field(RMF)framework and substituted into the Hamiltonian,which is calculated using the complex momentum representation(CMR).Considering even-even titanium isotopes as an example,this study investigated various properties,including the resonant states of neutron-rich nuclei in the RMF-CMR model,and used them to describe the binding energy.The abrupt decrease in the two-neutron separation energy(S_(2n))corresponds to the traditional magic number.The resonant and bound states are simultaneously exposed in the complex moment plane,where the continuum is along the integration contour.The four oblate neutron-rich nuclei^(72-78)Ti are weakly bound or resonant because their Fermi energies are approximately 0 MeV.The root-meansquare(RMS)radii of these nuclei increase suddenly compared with those of others(neutron number N<48).Moreover,^(78)Ti and^(76)Ti are determined as drip-line nucleons by the value of S_(2n) and the energy levels,respectively.Finally,the weak-bounded character can be represented by diffuse density probability distributions. 展开更多
关键词 Resonant states Self-consistent potential complex momentum representation
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Exploration of the ground state properties of neutron-rich sodium isotopes using the deformed relativistic mean field theory in complex momentumrepresentations with BCS pairings
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作者 罗雨轩 刘泉 郭建友 《Chinese Physics C》 SCIE CAS CSCD 2024年第4期115-129,共15页
This study explores the ground-state characteristics of neutron-rich sodium isotopes,encompassing two-neutron separation energies,root-mean-square radii,quadrupole moments of proton and neutron distributions,single-pa... This study explores the ground-state characteristics of neutron-rich sodium isotopes,encompassing two-neutron separation energies,root-mean-square radii,quadrupole moments of proton and neutron distributions,single-particle levels of bound and resonant states,and neutron density distributions and shapes.Simultaneously,special attention is paid to the distinctive physical phenomena associated with these isotopes.The deformed relativistic mean field theory in complex momentum representations with BCS pairings(DRMF-CMR-BCS)employed in our research provides resonant states with real physics,offering insights into deformed halo nuclei.Four effective interactions(NL3,NL3^(*),PK1,and NLSH)were considered to assess the influence of continuum and deformation effects on halo structures.Calculations for odd-even nuclei ^(35–43)Na revealed the dependence on the chosen effective interaction and number of considered resonant states.Neutron occupation patterns near the Fermi surface,particularly in orbitals 1/2^(−)_(3) and 3/2^(−)_(2),were determined to be crucial in halo formation.The study provided detailed insights into the density distributions,shape evolution,and structure of neutron-rich sodium isotopes,contributing valuably to the field of nuclear physics. 展开更多
关键词 relativistic mean field complex momentum representations resonant states halo nuclei
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Exploring the halo phenomena of medium-mass nuclei having approximately Z=40 with point-coupled parameters in complex momentum representations 被引量:1
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作者 Yao-Wu Chu Tai-Hua Heng 《Chinese Physics C》 SCIE CAS CSCD 2021年第7期240-246,共7页
To explore the properties of neutron-rich nuclei with approximately 40 protons,the density-dependent point coupling(DD-PC1)effective interaction parameter is adopted in the relativistic mean-field theory with the comp... To explore the properties of neutron-rich nuclei with approximately 40 protons,the density-dependent point coupling(DD-PC1)effective interaction parameter is adopted in the relativistic mean-field theory with the complex momentum representation(RMF-CMR).The calculated two-neutron separation energy(S_(2n))and root-mean-square(rms)radii support the halo structure that appear in Mo and Ru isotopic chains.Besides,the neutron skin structures appear in Kr and Sr isotopes.The conclusions drawn are also supported by the single-particle energy levels and their occupancy probability and density distribution.Particularly,the energy levels,which reduce to bound states or are approximately 0 MeV with a small orbital angular momentum,are suggested to provide the primary contribution to increasing the neutron radius.Moreover,the single-particle energy levels significantly reflect the shell structure.In addition,the neutron drip line nuclei for Kr,Sr,Mo,and Ru elements are proposed via the changes in S_(2n). 展开更多
关键词 ground state properties complex momentum representation halo phenomena
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Exploration of resonances by using complex momentum representation
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作者 田亚娟 衡太骅 +2 位作者 牛中明 刘泉 郭建友 《Chinese Physics C》 SCIE CAS CSCD 2017年第4期88-93,共6页
Resonance research is a hot topic in nuclear physics,and many methods have been developed for resonances.In this paper,we explore resonances by solving the Schrodinger equation in complex momentum representation,in wh... Resonance research is a hot topic in nuclear physics,and many methods have been developed for resonances.In this paper,we explore resonances by solving the Schrodinger equation in complex momentum representation,in which the bound states and resonant states are separated completely from the continuum and exposed clearly in the complex momentum plane.We have checked the convergence of the calculations on the grid numbers of the Gauss-Hermite quadrature and the Gauss-Legendre quadrature,and the dependence on the contour of momentum integration.Satisfactory results are obtained.^17O is chosen as an example,and we have calculated the bound and resonant states to be in excellent agreement with those calculated in the coordinate representation. 展开更多
关键词 single-particle levels resonant states complex momentum representation
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Complex Matter Space and Relativistic Quantum Mechanics
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作者 Reza Ahangar 《Applied Mathematics》 2014年第21期3401-3410,共10页
The Special Relativity Theory cannot recognize speed faster than light. New assumption will be imposed that matter has two intrinsic components, 1) mass, and 2) charge, that is M = m + iq. The mass will be measured by... The Special Relativity Theory cannot recognize speed faster than light. New assumption will be imposed that matter has two intrinsic components, 1) mass, and 2) charge, that is M = m + iq. The mass will be measured by real number system and charged by an imaginary unit. This article presents a Complex Matter Space in Relativistic Quantum Mechanics. We are hoping that this approach will help us to present a general view of energy and momentum in Complex Matter Space. The conclusion of this article on Complex Matter Space (CMS) theory will lead help to a better understanding toward the conversion of mass and energy equation, unifying the forces, and unifying relativity and quantum mechanics. 展开更多
关键词 complex MATTER complex MASS complex ENERGY and momentum
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Formulae for Energy and Momentum of Relativistic Particle Regular at Zero-Mass State
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作者 Robert M Yamaleev 《Journal of Modern Physics》 2011年第8期849-856,共8页
In this paper we substantiate a necessity of introduction of a concept the counterpart of rapidity into the framework of relativistic physics. It is shown, formulae for energy and momentum defined via counterpart of r... In this paper we substantiate a necessity of introduction of a concept the counterpart of rapidity into the framework of relativistic physics. It is shown, formulae for energy and momentum defined via counterpart of rapidity are regular near the zero-mass and speed of light states. The representation for the energy-momentum is realized as a mapping from the massless-state onto the massive one which looks like as a 'q'-deformation. Quantization of the energy, momentum and the velocity near the light-speed is presaged. An analogue between the relativistic dynamics and the statistical thermodynamics of a micro-canonical ensemble is brought to light. 展开更多
关键词 RELATIVISTIC Dynamics complex ALGEBRA RAPIDITY ENERGY-momentum Background ENERGY Statistical Thermodynamics.
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Energy-Momentum Density of Non-Diagonal Bianchi Type Space-Time in General Relativity and Teleparallel Gravity
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作者 Ragab M. Gad Haifaa A. Alharbi 《Journal of Applied Mathematics and Physics》 2021年第9期2355-2375,共21页
We calculated the energy-momentum density of non-diagonal Bianchi type space-time in two different theories of gravity, General relativity (GR) and the theory of Teleparallel gravity (TG). Firstly, by applying Einstei... We calculated the energy-momentum density of non-diagonal Bianchi type space-time in two different theories of gravity, General relativity (GR) and the theory of Teleparallel gravity (TG). Firstly, by applying Einstein, Landau-Lifshitz, Bergmann-Thomson and M<span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">&#248;</span></span></span>ller prescriptions, using double index complexes in <strong>GR</strong>. Secondly, in the frame work of <strong>TG</strong>, we used the energy momentum complexes of Einstein, Bergmann-Thomson and Landau-Lifshitz. We also study the spacial cases of non-diagonal Bianchi type space-time <strong>BII</strong>, <strong>BVIII</strong> and <strong>BIX</strong>. We obtained the same energy-momentum density components for Einstein and Bergmann-Thomson prescriptions for the above four mentioned space-times that we considered in our work. Also, we found that the energy density component in M<span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">&#248;</span></span></span>ller prescription is zero for all Bianchi types space-times in GR. Furthermore, we show that if the metric components are functions of time t alone, then the total gravitational energy is identically zero. 展开更多
关键词 Energy-momentum Densities Double Index complexes Teleparallel Gravity Bianchi Type Space Time
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守恒性平面二维水流数学模型的研究 被引量:27
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作者 余明辉 袁雄燕 +2 位作者 刘合翔 刘俊涛 余飞 《武汉大学学报(工学版)》 CAS CSCD 北大核心 2002年第3期1-4,共4页
基于平面二维非恒定水流方程 ,结合实际应用需要 ,建立了一种守恒性较好的平面二维水流数学模型 ,并在概化河道和某一天然河道上对所建立的模型进行了验证 ,对验证结果和模型的性能作出了分析和评价 ,证明所建立的模型能处理复杂的边界... 基于平面二维非恒定水流方程 ,结合实际应用需要 ,建立了一种守恒性较好的平面二维水流数学模型 ,并在概化河道和某一天然河道上对所建立的模型进行了验证 ,对验证结果和模型的性能作出了分析和评价 ,证明所建立的模型能处理复杂的边界条件 ,并能保证水量和动量守恒 。 展开更多
关键词 复杂边界 水量守恒 动量守恒 水流数学模型
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顺直河道漫滩水流滩槽流量分配的计算 被引量:4
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作者 王韦 蔡金德 《成都科技大学学报》 EI CAS CSCD 1990年第6期69-75,共7页
对于顺直河道漫滩水流,本文在总结现有的滩槽流量分配计算方法的基础上、提出了两种新的计算方法—断面叠加法和谢汉祥修正法。室内及野外资料的验证表明,本文方法具有较高的精度。
关键词 复式河槽 漫滩水流 流量分配 计算
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内燃机油清净剂复配实验的模拟与预测
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作者 仝秋红 王毓民 姚顽强 《润滑与密封》 CAS CSCD 北大核心 2006年第8期109-111,共3页
探讨了汽车内燃机油清净剂复配实验的模拟与预测。首先实验研究了T102、T106、T113的复配性能,获得原始数据,然后采用附加动量法、变学习率算法以及动量法与自适应学习率组合算法分别对优化后的BP神经网络进行训练,对实验进行模拟与预... 探讨了汽车内燃机油清净剂复配实验的模拟与预测。首先实验研究了T102、T106、T113的复配性能,获得原始数据,然后采用附加动量法、变学习率算法以及动量法与自适应学习率组合算法分别对优化后的BP神经网络进行训练,对实验进行模拟与预测。结果表明,采用附加动量法无法达到预测目标,而采用动量法与自适应学习率组合算法对清净剂复配实验有较好的模拟与预测。 展开更多
关键词 内燃机油 清净剂复配 附加动量算法 自适应学习率算法 BP网络
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虹的理论 被引量:1
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作者 胡波 《纺织基础科学学报》 1993年第4期362-367,共6页
综述了虹的笛卡尔理论、艾里理论、米氏理论和复角动量理论,并对它们进行了评论和比较。
关键词 笛卡尔光线 高级虹 附属虹 虹积分
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强非局域介质中复宗量厄米-高斯型空间光孤子
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作者 王形华 陈荣泉 王清 《量子电子学报》 CAS CSCD 北大核心 2022年第3期459-466,共8页
不同阶数复宗量厄米-高斯光束具有不同的光强和相位分布,当阶数增大时,涡旋奇点个数增加,其个数与阶数相等,同时光束束宽和椭圆率也随之增大。利用分步傅里叶法数值模拟了复宗量厄米-高斯光束在强非局域介质中的传输,发现初始功率不等... 不同阶数复宗量厄米-高斯光束具有不同的光强和相位分布,当阶数增大时,涡旋奇点个数增加,其个数与阶数相等,同时光束束宽和椭圆率也随之增大。利用分步傅里叶法数值模拟了复宗量厄米-高斯光束在强非局域介质中的传输,发现初始功率不等于临界功率时,可得到振荡传输的呼吸子;若光束的初始功率等于临界功率,可得到稳定的孤子。进一步研究表明,孤子光强的旋转方向取决于参量ξ中虚部前面的符号;不同阶数孤子的临界功率相同,轨道角动量却随着阶数的增加而增大;在添加噪声后,复宗量厄米-高斯型孤子依然能稳定传输。 展开更多
关键词 非线性光学 强非局域介质 分步傅里叶法 复宗量厄米-高斯光束 轨道角动量
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复杂结构井数值模拟分段耦合模型
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作者 安永生 宋扬 李振泉 《中国石油大学学报(自然科学版)》 EI CAS CSCD 北大核心 2013年第4期109-113,共5页
针对复杂结构井的油藏渗流特征和井筒流动特点,分别建立油藏质量守恒方程、井筒质量守恒方程和井筒动量方程,采用井筒分段的方法对复杂结构井进行分段、编号,并与油藏网格相匹配,结合数值模拟矩阵'镶边'处理方法实现复杂结构井... 针对复杂结构井的油藏渗流特征和井筒流动特点,分别建立油藏质量守恒方程、井筒质量守恒方程和井筒动量方程,采用井筒分段的方法对复杂结构井进行分段、编号,并与油藏网格相匹配,结合数值模拟矩阵'镶边'处理方法实现复杂结构井油藏和井筒的耦合,利用全隐式方法进行求解。以鱼骨状分支井为例进行计算分析。结果表明,复杂结构井分段耦合模型能够充分体现油藏渗流和井筒变质量流的相互影响,改进后的数值模拟软件可以满足复杂结构井生产动态模拟的需求。 展开更多
关键词 油藏 复杂结构井 数值模拟 分段耦合模型 质量守恒 动量守恒
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复动量格林函数方法对n-α散射研究
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作者 王晓伟 郭建友 《物理学报》 SCIE EI CAS CSCD 北大核心 2019年第9期93-100,共8页
在复动量表象下引入格林函数,建立了复动量格林函数方法.把这种方法应用于n-α散射系统,计算其散射相移.提取n-α系统的共振态并研究共振态对能级密度、相移和散射截面的贡献.在不引入任何非物理参数的前提下,离散化薛定谔积分方程得到... 在复动量表象下引入格林函数,建立了复动量格林函数方法.把这种方法应用于n-α散射系统,计算其散射相移.提取n-α系统的共振态并研究共振态对能级密度、相移和散射截面的贡献.在不引入任何非物理参数的前提下,离散化薛定谔积分方程得到束缚态、共振态和连续谱.通过分析散射态物理量可以更好地理解共振态以及非共振连续谱态.在n-α系统中的成功应用,证明了该方法的正确性. 展开更多
关键词 复动量格林函数 共振态 散射相移 截面
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Fundamental Way of Charge Formation and Relation between Gravitational Field and Electromagnetic Field
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作者 Mukul Chandra Das Rampada Misra 《International Journal of Astronomy and Astrophysics》 2012年第2期97-100,共4页
A complex motion and complex momentum due to relativistic phenomenon has been deduced in this paper. This procedure leads to explain the generation of a field which is the result of energy momentum complexity (tensor)... A complex motion and complex momentum due to relativistic phenomenon has been deduced in this paper. This procedure leads to explain the generation of a field which is the result of energy momentum complexity (tensor). In this work, a form of complex momentum of photon has been derived. This momentum reveals the construction of electromagnetic field. These procedures have been applied to explain the electromagnetic field of fundamental charged particle and leads to the assumption of fundamental charge. In this works trial would be made to derive a relation between gravitational field and electromagnetic field. 展开更多
关键词 Superimposed SPINS complex momentum
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融合动量项的步长自适应盲源分离算法 被引量:2
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作者 李春腾 蒋宇中 +1 位作者 刘芳君 张曙霞 《海军工程大学学报》 CAS 北大核心 2019年第3期107-112,共6页
为进一步缓解盲源分离算法收敛速度与稳态误差之间的矛盾,首先在自然梯度算法的基础上,通过融合动量项改善算法的收敛速度,基于分离性能指标的步长自适应减小稳态误差;然后,给出了所提算法的模型图,同时考虑分离性能和计算复杂度,选择... 为进一步缓解盲源分离算法收敛速度与稳态误差之间的矛盾,首先在自然梯度算法的基础上,通过融合动量项改善算法的收敛速度,基于分离性能指标的步长自适应减小稳态误差;然后,给出了所提算法的模型图,同时考虑分离性能和计算复杂度,选择合适的融合动量项算法,并设计了算法的近似最优参数,有效避免了算法的分段收敛;最后,合理选择步长与动量项的权重系数,有效改善了分离性能与收敛速度。仿真结果表明:该算法在一定程度上缓解了上述矛盾,并具有较低的计算复杂度。 展开更多
关键词 盲源分离 自然梯度算法 动量项 自适应步长 分离性能指标 计算复杂度
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复杂电磁波的动量密度
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作者 董正高 《大学物理》 2022年第12期26-30,35,共6页
对均匀平面电磁波的情况,坡印廷矢量所描绘的纵向传播动量图像清晰、简明.但对于具有涡旋相位或非均匀偏振态的复杂电磁波来说,坡印廷矢量能体现更丰富的动量内涵.本文基于电磁波的相量表达方法,从坡印廷矢量出发,在傍轴情况下分析了复... 对均匀平面电磁波的情况,坡印廷矢量所描绘的纵向传播动量图像清晰、简明.但对于具有涡旋相位或非均匀偏振态的复杂电磁波来说,坡印廷矢量能体现更丰富的动量内涵.本文基于电磁波的相量表达方法,从坡印廷矢量出发,在傍轴情况下分析了复杂电磁波的纵向传播动量以外的横向轨道动量、横向自旋动量,列举了几种典型电磁波中不同物理起因的横向动量特征,并结合相位分布图像进行了解释. 展开更多
关键词 坡印廷矢量 动量密度 轨道动量 自旋动量 复杂电磁波
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复动量表象方法对丰中子Cr 同位素奇特结构的研究
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作者 曹雪能 郭建友 《原子核物理评论》 CAS CSCD 北大核心 2023年第1期17-24,共8页
奇特核的研究是核物理中最有趣的前沿课题之一。中等质量核中是否存在晕现象,目前的研究相对较少。复动量表象(CMR)方法可以用来探索原子核中的奇特结构。连续谱阈值附近的共振态在奇特现象的形成中起着重要的作用。利用相对论点耦合框... 奇特核的研究是核物理中最有趣的前沿课题之一。中等质量核中是否存在晕现象,目前的研究相对较少。复动量表象(CMR)方法可以用来探索原子核中的奇特结构。连续谱阈值附近的共振态在奇特现象的形成中起着重要的作用。利用相对论点耦合框架下的复动量表象(RMFPC-CMR)方法研究了丰中子Cr同位素中的奇特结构,得到的非常接近于零的双中子分离能和迅速增大的中子均方根半径表明在靠近中子滴线的Cr同位素中存在晕结构。从获得的单粒子能级、费米面附近价核子占据几率、中子和质子密度分布以及各能级对原子核密度的贡献可以发现3s1/2和2d3/2能级的占据有利于中子晕的形成。研究发现,低角动量弱束缚能级对异常增大的半径和弥散密度分布有显著的贡献,这导致靠近中子滴线的76-82Cr是中子晕核。这一预测结果对在实验中探索中等质量区的晕核具有一定的参考价值。 展开更多
关键词 相对论点耦合模型 复动量表象方法 单粒子能级
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