Diffraction of electromagnetic waves by a radially inhomogeneous plasma sphere and cylinder

Radiophysics and Quantum Electronics -     

Scattering of polarized electromagnetic radiation by turbulent fluctuations of a high-temperature plasma

An investigation was made of the process of Raman scattering of polarized electromagnetic radiation by turbulent fluctuations in a plasma with a magnetic field. It was found that a turbulent plasma with a magnetic field scatters left- and right-handed circularly polarized radiation in different ways. The possibility is analyzed of using the results obtained in order to provide diagnostics for different plasma characteristics in thermonuclear fusion devices employing magnetic plasma confinement. Institute of Solar and Terrestrial Physics, Siberian Branch of the Russian Academy of Sciences. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 4, pp. 102–107, April, 1998.     

Scattering of a plane electromagnetic wave by an infinite wedge with a truncated circular cylinder coated coaxially with a magnetodielectric layer

We formulate and solve the problem of scattering of a plane electromagnetic wave by an infinite, perfectly conducting wedge with a truncated, perfectly conducting circular cylinder which is coated coaxially with a magnetodielectric layer and located along the wedge edge. The rigorous solution is obtained and reduced to a system of linear algebraic equations of the second kind for unknown coefficients of Fourier expansions of the scattered field. The results of calculating the scattered field in the far zone with a specified accuracy are presented for the case of an H-polarized wave. It is shown that for certain values of the electric radius of the cylinder, the backscattering cross section of such a structure has pronounced maxima.     

弹性波由吸收圆柱的散射

研究了弹性纵波照射粘弹圆柱产生的稳态散射,导出了简洁的散射场解析表达式,数值计算了吸收和非吸收圆柱散射作的散射截面。结果表明,对高速圆柱散射体,散射截面随Ka增加是光滑振荡变化的,吸收圆柱和非吸收圆柱散射截面特征类似。对低速圆柱散射体,振荡变化的散射截面上叠加有一系列狭窄峰,散射圆柱和周围介质的对应速度差别越大,这种狭窄峰也越多,越靠近极值附近,这些狭窄峰越密,圆柱存在吸收衰减时将降低这些狭窄峰。当散射圆柱和周围介质对应的纵波速度和横波速度差别很小时,散射截面为非规则的小幅度的谐振。     

Scattering of electromagnetic waves by a chiral cylinder

We consider the problem of three-dimensional diffraction of electromagnetic waves excited by an elementary source on a chiral infinite cylinder of arbitrary radius. Effective scattering cross sections of a chiral cylinder in the case of two-dimensional diffraction are numerically analyzed. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 51, No. 10, pp. 872–883, October 2008.     

Scattering of electromagnetic waves by a layer of air plasma surrounding a conducting cylinder

In this paper, the total scattering and back-scattering cross-sections (respectively represented by and _b) of an air plasma layer surrounding a conducting cylinder are studied. The plasma layer can be turned ON and OFF to allow for a comparison between the scattering cross-section of the bare cylinder and the plasma covered cylinder. The plasma layer is generated at atmospheric pressure, which results in a very highly collisional case. The scattered fields are calculated using a cylindrical expansion, with coefficients satisfying the appropriate boundary conditions, and which are a function of the refractive index of the air plasma. The results of our study are presented as plots of the total scattering cross-section, , and back-scattering cross-section, _b, versus frequency. The scattering cross-section gives an average characteristic of the scattering process from obstacles. Once the scattering cross-section is known, the actual scattered energy per unit length per second can be calculated by multiplying by the incident energy per unit area per second.     

On lower hybrid wave scattering by plasma density fluctuations

The author thanks R. Klíma for bringing the problem of wave scattering to the author's attention. Further, the author is obliged to J. Preinhaelter for his kind permission to use the computed spectra /3/ (full curves, figs. 1, 2) prior to publication.     

Scattering cross-section of an inhomogeneous plasma cylinder

Scattering of em waves by the plasma cylinder is of significance in radar target detection, plasma diagnosis, etc. This paper discusses the general method tocalculate the scattering cross-section of em waves from a plasma cylinder which is radially inhomogeneous and infinitely long. Numerical results are also provided for several plasma density profiles. The effect of the electron density distribution on the scattering cross-section is investigated.     

Scattering of a Gaussian electromagnetic beam by a thin semiconducting cylinder

The scattering of a three-dimensional Gaussian electromagnetic beam by a thin (compared to the wavelength) semiconducting cylinder of infinite length is considered. Expressions for the scattered field and for the current induced in the cylinder are obtained. A numerical analysis of the distribution of the secondary current along the cylinder axis was made. It is shown that the dependence of the induced current on the distance along the cylinder axis becomes Gaussian as the aperture of the incident beam is increased.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 1, pp. 78–80, January, 1991.