悬链曲面上的点粒子动力学及扩展空间约束系统量子化

扩张型正则量子化方案的核心内容是位置、动量以及哈密顿量同时量子化. 通过分析悬链面上粒子的扩张型正则量子化方案, 并且与薛定谔理论进行比较, 发现内禀几何中二维悬链面给不出与薛定谔理论相一致的结果, 而考虑将二维悬链面嵌入在三维欧氏空间之后, 还需要将正则量子化方案进行扩张, 可以得到体系的几何势能和几何动量, 并与薛定谔理论相一致.     

On the determination of the position of the energy level of surface recombination centres

A detailed analysis of the dependence of the surface recombination velocitys on the surface potential _s leads to the conclusion that the position of the surface recombination level with respect to the centre of the energy gapE _t -E _i does not coincide with the valueq _s *, while the surface recombination velocitys decreases to half its maximum value. The difference between the two quantities is negligible only when the width of the curves( _s ) between the points corresponding to the valuess=1/2s _max is greater than 8kT.

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s _s , E _t -E _{i s} , s . , s( _s ) , s=1/2s _max, 8kT.

     

Study of the XYZ states at the BESIII

With its unique data samples at energies of 3.8–4.6 GeV, the BESIII experiment made a significant contribution to the study of charmonium and charmonium-like states, i.e., the XYZ states.We review the results for observations of the Z_c(3900) and Z_c(4020) states, the X(3872) in e⁺e⁻ annihilation, and charmonium ψ(1³D₂) state, as well as measurements of the cross-sections of ωχ_cJ and ηJ/ψ, and the search for e⁺e⁻→ γχ_cJ and γY (4140). We also present data from BESIII that may further strengthen the study of the XYZ and conventional charmonium states, and discuss perspectives on future experiments.     

On the problem of the phase shifts of reflected light

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On the problem of the phase shifts of reflected light

The paper solves the topical question of phase shifts when light is reflected. By introducing the reflection tensor and its transformation it was found that all phase shifts hitherto given in the literature can be used. It was proved that when different phase shifts are used the corresponding unit vectors must be oriented. If an arbitrary coordinate system and the relations pertaining to it are used consistently it is not possible by calculation or experiment to arrive at contradictory results.

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. , , . .: , 1961. . 45–49 . . , .. . , .     

On the problem of the permittivity dispersion of barium titanate

The complex permittivity of multidomain single crystals of BaTiO₃ was measured in the decimetre and centimetre wave bands and it was proved that in this frequency region there is dispersion of the permittivity. Apparatus for measuring the permittivity of substances with a high is described and the influence of the inhomogeneity of the field in the sample on the characteristics of the cavity resonator is calculated. Present theories of the high-frequency properties of BaTiO₃ are discussed from the point of view of the experimental results.

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BaTiO₃ , . . BaTiO₃.