scholarly journals Two-Dimensional Scattering by a Homogeneous Gyrotropic-Type Elliptic Cylinder

2016 ◽  
Vol 5 (3) ◽  
pp. 106
Author(s):  
A. K. Hamid ◽  
F. Cooray
Keyword(s):  
Cross Sections ◽  
Plane Electromagnetic Wave ◽  
Separation Of Variables ◽  
Elliptic Cylinder ◽  
Wave Functions ◽  
Two Dimensional ◽  
Vector Wave ◽  
Expansion Coefficients ◽  
Scattering Cross Sections ◽  
Uniform Plane

The separation of variables procedure has been employed for solving the problem of scattering from an infinite homogeneous gyrotropic-type (G-type) elliptic cylinder, when a uniform plane electromagnetic wave perpendicular to its axis, illuminates it. The formulation of the problem involves expanding each electric and magnetic field using appropriate elliptic vector wave functions and expansion coefficients. Imposing suitable boundary conditions at the surface of the elliptic cylinder yields the unknown expansion coefficients related to the scattered and the transmitted fields. To demonstrate how the various G-type materials and the size of the cylinder affects scattering from it, plots of scattering cross sections are given for cylinders having different permittivity/permeability tensors and sizes.

scholarly journals Semi-classical bounds on scattering cross sections in two dimensional magnetic fields

1997 ◽  
Vol 147 ◽  
pp. 25-61
Author(s):  
Hideo Tamura
Keyword(s):  
Magnetic Fields ◽  
Energy Range ◽  
Cross Sections ◽  
Classical Limit ◽  
Uniform Boundedness ◽  
Classical Dynamics ◽  
Two Dimensional ◽  
Total Cross Sections ◽  
Scattering Cross ◽  
Scattering Cross Sections

AbstractWe prove the uniform boundedness of averaged total cross sections or of quantities related to scattering into cones in the semi-classical limit for scattering by two dimensional magnetic fields. We do not necessarily assume that the energy under consideration is in a non-trapping energy range in the sense of classical dynamics.

SCATTERING BY A PERFECTLY CONDUCTING CYLINDER IN A GYROELECTRIC MEDIUM: NUMERICAL RESULTS

1964 ◽  
Vol 42 (5) ◽  
pp. 860-872 ◽  
Author(s):  
S. R. Seshadri
Keyword(s):  
Electromagnetic Wave ◽  
Circular Cylinder ◽  
Cross Sections ◽  
Plane Electromagnetic Wave ◽  
Numerical Results ◽  
Gyrotropic Medium ◽  
Magnetic Vector ◽  
Scattering Cross ◽  
Incident Plane ◽  
Scattering Cross Sections

The numerical results on the various scattering cross sections of a perfectly conducting circular cylinder embedded in a gyrotropic medium are presented for the case in which both the gyrotropic axis and the magnetic vector of the incident plane electromagnetic wave are parallel to the axis of the cylinder.

Elastic wave scattering by a circular crack

1982 ◽  
Vol 308 (1502) ◽  
pp. 167-198 ◽  
Keyword(s):  
Cross Sections ◽  
Circular Crack ◽  
Integral Equation Method ◽  
Infinite Matrix ◽  
Far Field ◽  
Direct Integral ◽  
Elastic Wave Scattering ◽  
The Matrix ◽  
Expansion Coefficients ◽  
Scattering Cross Sections

The scattering of waves by a circular crack in an elastic medium is solved by a direct integral equation method. The solution method is based on expansion of stresses and displacements on the crack surface in terms of trigonometric functions and orthogonal polynomials. The expansion coefficients are related through an infinite matrix, and by contour integration the matrix elements are expressed in terms of finite integrals. The scattered far field is expressed explicitly in terms of simple functions and the displacement expansion coefficients. The system of equations is solved numerically, and extensive results are given both in the form of maps of the scattered far field and as scattering cross sections. Neither the method nor the specific results are restricted by any assumptions of symmetry.

Scattering by a thin multicoated perfectly conducting spherical shell with a circular aperture

1992 ◽  
Vol 70 (2-3) ◽  
pp. 164-172 ◽  
Author(s):  
R. A. Said ◽  
M. Hamid
Keyword(s):  
Spherical Shell ◽  
Cross Sections ◽  
Spherical Wave ◽  
Least Square ◽  
Circular Aperture ◽  
Modal Expansion ◽  
Scattering Coefficients ◽  
Expansion Coefficients ◽  
Scattered Fields ◽  
Scattering Cross Sections

An analytic solution is presented for the problem of an infinitely thin perfectly conducting spherical shell with a circular aperture of arbitrary angle cut into the shell, filled with a dielectric, and coated by different thicknesses of spherical dielectric layers. The fields in all regions are expanded in terms of spherical wave functions and the boundary conditions of the continuity of the tangential fields at the dielectric–dielectric and dielectric–free-space boundaries are applied to express the expansion coefficients of the first dielectric layer in terms of the scattering coefficients. To approximate the modal expansion coefficients, the least-square error method is applied to the equations resulting from matching the fields through the aperture. Different numerical results for the simple case of a single coating layer are obtained in the form of amplitude patterns for the aperture and scattered fields versus angle as well as the backward- and forward-scattering cross sections for different loadings as functions of cavity size.

Multiple scattering by a linear array of conducting spheres

1990 ◽  
Vol 68 (10) ◽  
pp. 1157-1165 ◽  
Author(s):  
A-K. Hamid ◽  
I. R. Ciric ◽  
M. Hamid
Keyword(s):  
Multiple Scattering ◽  
Cross Sections ◽  
Linear Array ◽  
Plane Electromagnetic Wave ◽  
Spherical Wave ◽  
Approximate Solutions ◽  
Addition Theorem ◽  
Wave Functions ◽  
Coordinate Systems ◽  
Conducting Spheres

The problem of multiple scattering of a plane electromagnetic wave incident on N closely spaced perfectly conducting spheres is solved analytically by expanding the incident and scattering fields in terms of an appropriate set of vector spherical wave functions. To impose the boundary conditions, the scattered field from one sphere is expressed in coordinate systems attached to the others by using the translation addition theorem. An approximate solution is obtained to solve for the scattering by N small spheres. Numerical results for the normalized backscattering and bistatic cross sections for systems of spheres show that the agreement between the analytic and approximate solutions is better for larger electrical distances between neighbouring spheres.

Radiation characteristics of a slot antenna on a conducting prolate spheroid

1995 ◽  
Vol 73 (5-6) ◽  
pp. 376-385 ◽  
Author(s):  
M. Zhang ◽  
A. A. Sebak
Keyword(s):  
Prolate Spheroid ◽  
Wave Functions ◽  
Slot Antenna ◽  
Published Data ◽  
System Of Equations ◽  
Prolate Spheroidal ◽  
Radiation Characteristics ◽  
Vector Wave ◽  
Slot Length ◽  
Expansion Coefficients

In this paper, the radiation characteristics of an asymmetrical slot antenna on a conducting prolate spheroid are considered. The radiated fields are expanded in terms of prolate-spheroidal vector wave functions. The unknown expansion coefficients are determined by a system of equations derived from the boundary conditions. Numerical results for radiation patterns and conductance are obtained and compare well with published data for a slotted sphere. The effect of the slot length and the shape of the spheroid on the magnitude of the radiated field and radiation conductance is also presented.

Theory of low temperature spin exchange scattering for a physisorbed two-dimensional gas of hydrogen atoms

1983 ◽  
Vol 61 (7) ◽  
pp. 1042-1045 ◽  
Author(s):  
M. Morrow ◽  
A. J. Berlinsky
Keyword(s):  
Cross Sections ◽  
Spin Exchange ◽  
Relaxation Times ◽  
Three Dimensional ◽  
Two Dimensional ◽  
Hydrogen Atoms ◽  
Transverse Relaxation ◽  
Exchange Scattering ◽  
The One ◽  
Scattering Cross Sections

Calculations are presented of the two-dimensional scattering cross sections which are required to evaluate the longitudinal and transverse relaxation times T1 and T2 and the frequency shift Δν due to spin exchange collisions between H atoms physisorbed on a surface. The results are used to interpret the recent measurements by Crampton and co-workers of the relaxation time T1 for H atoms in the presence of solid H2 walls. New results are also presented for T1, due to three-dimensional scattering in the gas, using a more recent triplet H–H potential than the one previously employed by Berlinsky and Shizgal.

Inelastic Electron Scattering from 18O

1971 ◽  
Vol 49 (22) ◽  
pp. 2743-2753 ◽  
Author(s):  
J. L. Groh ◽  
R. P. Singhal ◽  
H. S. Caplan ◽  
B. S. Dolbilkin
Keyword(s):  
Electron Scattering ◽  
Cross Sections ◽  
Ground State ◽  
Transition Probabilities ◽  
Form Factors ◽  
Wave Functions ◽  
Inelastic Electron ◽  
Inelastic Electron Scattering ◽  
Momentum Transfer Range ◽  
Scattering Cross Sections

The inelastic electron scattering cross sections for the excitation of the levels in 18O lying below 6.0 MeV have been measured in the momentum transfer range 0.5 < q < 1.0 fm−1. Excitation of the following T = 1 levels was observed: 1.98 MeV (2+), 3.63 MeV (0+), 3.92 MeV (2+), 4.45 MeV (1−), 5.09 MeV (3−), 5.25 MeV (2+), and 5.33 MeV (0+). Estimates of transition probabilities to the ground state have been made through a parameterization of the data using the generalized Helm model. Longitudinal form factors calculated from the wave functions of Benson and Irvine show excellent agreement with the experimental form factors.

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