The shape of the nuclear spin-orbit potential

The recently observed strong state dependence of the nuclear spin-orbit splitting can be explained by a phenomenological spin-orbit potential which describes quantitatively the splittings of the 20 known single particle states in²⁰⁸Pb.     

单粒子本征波函数的对称性与势形状

以单核子在原子核三轴椭球形变势中运动的本征值方程为例,说明核形状决定了核势的形状,核势形状的对称性决定了在其势中运动的单粒子本征态的对称性.当核势形状的对称性随形变参量的改变而改变时,对应单粒子本征态对称性的改变,可以用量子力学中的表象变换来表现,也可以用波函数的表象变换来认识.此问题虽然来自于原子核结构理论,但其思想对于在原子、分子、团族粒子等量子体系中处于平均场中运动的独立粒子问题具有普遍意义.     

On the effect of the geometrical shape of a particle on threshold energy in erosion damage

The structural-temporal approach is used for analyzing the energy required for fracture. The behaviors of the threshold fracture energy in the impact of spherical and cylindrical particles against an elastic half-space are compared. It is shown that the threshold energy minimum can be attained using spherical particles. The plots of the dependence of the threshold energy on the impact duration and on the particle radius are constructed for the cases under investigation.     

PT violating single particle nuclear potential

We calculate aPT-odd one-loop meson radiative correction to the scattering amplitude of a nucleon on the external field of the nucleus. The nonrelativistic limit of this amplitude, Fourier transformed to the configuration space, can be interpreted as a single particlePT-odd potential for a valence nucleon. Bound state effects on this potential are evaluated and found to be negligible.     

The single particle potential in nuclear matter

The energy dependent real part of the optical potential for particles and holes in nuclear matter is calculated from a realistic nuclear hamiltonian that explains the nucleon-nucleon scattering data and equilibrium properties of nuclear matter. The variational method is used with Fermi-hypernetted and single-operator-chain summation techniques. The results are comparable with empirical Woods-Saxon well depths at energies ? 150 MeV. At higher energies the potential has a density dependence suggesting a “wine-bottle” shaped nucleon-nucleus potential.     

On the particle hardening in Cu-Cd alloy single crystals

The transmission electron microscopy of Cu-Cd single crystals deformed previously was performed to explain the hardening effect measured. The increment of the critical resolved shear stress is explained by the size misfit effect of the observed particles.     

Effects of single particle on shape phase transitions and phase coexistence in odd-even nuclei

A classical analysis of shape phase transitions and phase coexistence in odd-even nuclei has been performed in the framework of the interacting boson-fermion model. The results indicate that the effects of a single particle may influence different types of transitions in different ways. Especially, it is revealed that phase coexistence can clearly emerge in the critical region and thus be taken as a indicator of the shape phase transitions in odd-even nuclei.     

单透镜几何参数的自动优化设计

研制了对各种形状单透镜几何参数进行优化的软件。单透镜自动优化设计软件的功能有：①确定合理的初始参数，修正不合理的原始参数；②若原始数据未给中心厚度，首先根据工艺因素，初步确定出中心厚度；③根据折射率ｎ、焦距ｆ、口径Ｄ、中心厚度ＣＴ确定透镜曲率半径；④在中心厚度的公差范围中，计算出焦距一定的情况下由中心厚度变化引起的半径可变化范围；⑤根据焦距误差范围，计算出一定厚度条件下半径的变化范围；⑥综合④、⑤两方面，按相应的函数关系求出半径总的变化范围；⑦在该半径变化范围内，从样板库中查找出符合要求的样板。⑧将所有符合要求的样板半径与其它技术参数综合起来考虑，自动优化平衡分析，选出工艺性能好、制造成本低、焦距误差最小的最优解。例如，可根据初始数据的实际情况，自动优选零件厚度与样板半径的最佳配对方案，以求最佳设计结果。⑨若在库存样板中没有查询到满足设计要求的样板，则以计算出的公称值作为设计结果，并在该结果前作上标记，以提醒工艺人员提前作好加工工艺准备工作。用本文所报告的设计方法，完成不同类型千余套单透镜光这参数设计的运行时间为十几分钟。该软件可与光学系统设计软件、光学零件绘图软件、光学工艺软件、光学零件在线管理软件、光学?     

Perturbative pseudospin symmetry limit with linear spin-orbit potential

The pseudospin symmetry (PSS) limits which conserve substantial spin-orbit splitting are investigated. It is found that while the strength of the spin-orbit potential as well as the spin-orbit splitting increase, the pseudospin doublets, e.g., 2p_3/2 and 1f_5/2 states, are always degenerate. Furthermore, by examining the perturbation corrections to the single-particle energies, the perturbative nature of the proposed PSS limits is also discussed.     

On the geometrical interpretation of solitons

Rigid body motion along helical space curves is shown to generate a class of nonlinear partial differential equations solvable by the two component inverse scattering phenomenology and the associated class of pseudopotentials, prolongation and Lie-algebraic structures. The results unify the various soliton interpretations.     

The role of spin-orbit potential in nuclear prolate-shape dominance

It is confirmed, in terms of the Woods-Saxon-Strutinsky method, that the spin-orbit potential plays a decisive role in the predominance of prolate deformation, which has been a long standing problem in nuclear physics. It is originated from the combined effects of the spin-orbit coupling and the diffused surface of the potential, in agreement with the previous work based on a more schematic Nilsson-Strutinsky method. The degree of prolate-shape dominance exhibits an oscillatory behavior with respect to the strength of spin-orbit potential and, the prolate-shape dominance is realized at the proper strength of the spin-orbit potential together with the standard surface diffuseness; this oscillatory behavior disappears in case of small diffuseness corresponding to ellipsoidal cavity. The calculated energy differences between oblate and prolate minima in this Letter are consistent with those of our extensive self-consistent calculations of the Hartree-Fock + BCS method with the Skyrme interaction.     

On the influence of spin-orbit scattering on the Kondo effect

It is shown that the hyperfine splitting of the levels 2s _1/2 and 2p _1/2 of atomic hydrogen has a measurable influence on the mixing of these levels in a weak electric field.     

On the discrete spectrum of spin-orbit Hamiltonians with singular interactions

We give a variational proof of the existence of infinitely many bound states placed below the continuous spectrum for spin-orbit Hamiltonians (including the Rashba and Dresselhaus cases) perturbed by measure potentials, thus extending results of J. Brüning, V. Geyler, K. Pankrashkin, J. Phys. A: Math. Theor. 40 F113–F117 (2007).     

On the geometrical aspects of electromagnetism,I

The trajectory of a charged test particle under a Lorentz force is obtained as the geodesic of a riemannian four dimensional manifold. Originally, the geodesic equation is nonlinear in some vector field A′_μ. The nonlinearity is traded in for the correct characteristic $\text{e}\text{m}$ of the test particle through a gauge condition, imposed upon A′_μ, which turns the geodesic into the fully covariant linear and gauge invariant Lorentz equation. Fitting the $\text{e}\text{m}$ ratio inside the gauge leaves F′_μν independent of $\text{e}\text{m}$ and allows its identification with the E.-M. tensor F_μν. This four dimensional approach allows the identification of the fifth coordinate used in Kaluza's geometrization |1,2|. The gauge function appears as the sum of Hamilton-Jacobi function plus an additional term, related to the “length” of the trajectory. It is this latter term which guarantees the correct “normalisation” of the $\text{e}\text{m}$ ratio.