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导出了无磁化无碰撞各向同性相对论正负电子对等离子体纵波的色散关系。使用逐次近似的标准技术,对两种极限情况下的纵波色散方程进行了解析研究。将完全色散方程进行变换,使它们完全适用于在需要完全相对论处理的温度范围内进行数值计算。用数值模拟方法得到了用解析方法不能得到的完全的色散曲线。     

The dispersion relation of the charge and current compensated relativistic electron beam-plasma system

Analysing the general dispersion relation numerically, the unstable regions of the relativistic electron-beam plasma system were determined. The external parameters were varied to ensure more effective instability excitations. The full charge and current compensation presumptions lead to new synchronism predictions. The return current's slow space charge wave and return current's slow cyclotron wave are synchronous with the plasma ion wave.     

Dispersion relation for longitudinal waves in a relativistic plasmas

Imre, Buti and others studied the longitudinal waves from the general dispersion relation. Here we have derived the dispersion relation for the longitudinal waves in relativistic plasmas, a result which cannot easily be brought in a physically more convenient form.     

On the Lorentz-invariant time-energy uncertainty relation for a relativistic photon

The time-energy uncertainty relation is discussed for a relativistic massless particle. The Lorentz-invariant uncertainty relation is obtained between the root-mean-square energy deviation and the scatter of registration time. The interconnection between this uncertainty relation and its classical analogue is established.     

A dispersion relation for gravitational radiation in a Schwarzschild background

A dispersion relation is derived for gravitational radiation emitted from an almost spherical object.     

Plasmon dispersion relation for a disordered interacting quasi-two-dimensional electron gas

The dispersion relation for plasma oscillations is considered for a quasi-two-dimensional interacting electron gas at zero temperature in the presence of randomly distributed impurities. Electron-impurity scattering is described in a relaxation time approximation which conserves local particle number density and electron-electron interactions beyond RPA are included by a static local field correction.     

APW dispersion relation for plasmon in metals

Following Ichikawa's technique we derived a dispersion relation for plasmons in metals using APW (Augmented Plane Wave) wave functions. The formula contained herein may be used to acquire information concerning the filling of the energy bands and so data needed in explaining electrical and magnetic properties of metals.     

Normal mode double-branch dispersion relation for metals within a variational calculation

In a previous note [1] a variational calculation was considered which describes volume plasmons in highdensity metals. We extend this calculation by considering a more flexible parametrization and show that, as a result, a splitting is obtained leading to two normal modes for each value of the transferred momentum q. The single particle excitations are responsible for the new structure. The strength and the energy of each mode determine its collective or single particle character for very small or very large values of q. The present results predict an appreciable redistribution of transition strength, in agreement with recent experimental findings.     

Nonlinear dispersion relation for surface plasmon at a metal-Kerr medium interface

The dispersion relation for the plasmon at the interface of a metal and a nonlinear Kerr medium is studied by applying a semi-analytic theory established in the literature. Explicit analytical results are obtained and are compared to those from a certain approximate treatment appeared in the literature. It is found that for large electric field strengths, both the dispersion relation and the surface plasmon frequency from the approximate treatment deviate significantly from those obtained in the exact approach, especially for the case with a negative Kerr susceptibility.     

A comparative study of the full dispersion relation, Compton dispersion relation, and Raman dispersion relation of a free-electron laser in helical wiggler and guiding magnetic fields

The full dispersion relation obtained for a free-electron laser in the presence of circularly polarized, periodic, static wiggler and guiding magnetic fields by the kinetic approach incorporating the particle trajectories is reduced to Compton and Raman regime approximations in the case of a tenuous electron beam. The temporal growth rate has been compared between the full dispersion relation and the Compton dispersion relation, as well as between the full dispersion relation and the Raman dispersion relation in the microwave region. The results show the maxima of growths in the full dispersion relation and the Compton dispersion relation, as well as the full dispersion relation and the Raman dispersion relation, are at the same locations, but the growth rates in both regimes are enhanced with respect to the full dispersion relation for the same plasma frequency and cavity parameters.     

Surface plasmon dispersion relation for spherical metal particles

Using the hydrodynamical model, we have obtained the surface plasmon dispersion relation for spherical metallic particles in the following two cases: (1) a sharp surface cut off in electron density and (2) a diffused electron density at the surface. The diffused density is modelled with a step function. The diffuse nature of the electron density at surface of the metal particle is necessary to understand the experimental result for particles with small radii. Shift in the absorption frequency is estimated and found to be small.     

A surface wave dispersion relation for non-local media

Conditions are obtained for the existence of surface waves at the interface of vacuum and a semi-infinite non-local medium whose inverse dielectric function is assumed to be symmetric in spatial coordinate in the direction perpendicular to the interface. It is shown that these conditions reduce to those obtained by Maradudin in the appropriate limits: for the isotropic case; and for no retardation.     

On the Barber dispersion relation for internal waves

We investigate the dispersive behaviour of internal waves supported by a density gradient in a fluid which has an upper boundary surface. By identifying a realistic model for the density gradient which leads to an analytically tractable internal wave eigenvalue equation we are able to verify the general applicability of, and to characterize the deviations from, the simple dispersion relation proposed recently by Barber. We also consider the effect of a linear background density variation superimposed on the localized pycnocline; this establishes a minimum frequency and wavenumber consistent with the propagation of the internal wave and leads to significant deviations from the Barber result.     

金属和Kerr非线性介质界面上表面等离子体激元的色散关系

从麦克斯韦方程组出发,结合边界条件,分别得到TM波和TE波在金属和Kerr非线性介质界面上表面等离子体激元的色散关系.由于非线性的存在,TM波的色散关系变得复杂,与光强、非线性系数有关.和线性情况一样,此界面不存在TE波.     

相对论行波管色散特性分析

 数值计算了一种填充等离子体的波纹波导结构的行波管，在强引导磁场下，被一环形相对论电子注驱动的小信号增益。详细地分析了等离子体的浓度、电子注的电压、电流及其在慢波结构中的传输位置对行波管的增益、带宽和中心频率的影响。     

Refractive index and material dispersion in relativistic electron optics

The refractive index and material dispersion associated with relativistic motion of electrons are calculated. Moreover, the wavelength dependence of refractive index is compared with the Sellmeier model for the index of refraction of lightwaves.