A comparative study of the scattering cross sections from incident plane wave acoustic waves on submerged evacuated and water‐filled elastic shells

2000 ◽  
Vol 107 (5) ◽  
pp. 2848-2848
Author(s):  
Herbert Uberall ◽  
Michael F. Werby
Keyword(s):  
Plane Wave ◽  
Comparative Study ◽  
Cross Sections ◽  
Acoustic Waves ◽  
Incident Plane Wave ◽  
Elastic Shells ◽  
Scattering Cross ◽  
Incident Plane ◽  
Scattering Cross Sections

Modification of scattering of waves by central loading

1968 ◽  
Vol 46 (24) ◽  
pp. 2755-2763 ◽  
Author(s):  
Chin-Lin Chen
Keyword(s):  
Plane Wave ◽  
Cross Section ◽  
Cross Sections ◽  
Normal Incidence ◽  
Physical Explanation ◽  
Lumped Element ◽  
Scattering Cross ◽  
Back Scattering ◽  
Conducting Wire ◽  
Scattering Cross Sections

The problem of the scattering of a plane wave by a long, thin, perfectly conducting wire is studied. The scatterer is loaded at its center by a lumped element. The effects of the loading on the scattering of waves are investigated. Numerical results are obtained for the case of normal incidence. The results show that for relatively short wires, the back-scattering cross sections may be modified effectively by central loading, while for longer wires, the modification is rather difficult to achieve. To nullify the back-scattering cross section completely, it is necessary to use active loading if kh > 3.6. A physical explanation is also presented.

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.

scholarly journals The motion of electrons in the static fields of hydrogen and helium

1932 ◽  
Vol 136 (830) ◽  
pp. 549-558 ◽  
Keyword(s):  
Plane Wave ◽  
Cross Sections ◽  
Spherical Wave ◽  
Static Field ◽  
Incident Plane Wave ◽  
Sound Waves ◽  
Angular Momenta ◽  
Incident Plane ◽  
Slow Electrons ◽  
Incident Waves

1. The scattering of electrons by atoms was first investigated by Born,* who adopted a method similar to that used by Huyghens and Kirchoff for the scattering of light by obstacles. Physically, Born’s approximation represents the integral of the amplitude of the secondary wavelets scattered from the incident plane wave only, and neglects the distortion of the plane wave by the atom. The perturbation of the incident wave will be smaller the larger the energy of the wave, so one would expect Born’s theory to be valid for high velocity impacts. Criteria for its validity have been given by Mott and Möller. The Born theory certainly breaks down for sufficiently low velocities as the cross-section curves obtained fall uniformly with increase of velocity of the incident electron beam, whereas the rare gas and alkali metal cross-sections (obtained from experiments) exhibit maxima and minima. At an impact there are present the incident waves and those scattered, both elastically and inelastically, and all these will interact. Born’s first approxi­mation neglects the effect of the scattered waves and the next approximation is obtained by neglecting only the inelastically scattered waves, and calculating exactly the elastic scattering of the electrons by the static field. This is done by the method of partial cross-sections which was developed by Faxen and Holtsmark and applied to the rare gases. The method consists in resolving the incident electrons into beams with different angular momenta, √{ l ( l +1)} h /2π, and a numerical solution of the wave equation is found which gives asymptotically the sum of an incident plane wave and a scattered spherical wave. The analysis is similar to that used by Rayleigh for the scattering of sound waves by obstacles. The incident electrons with l = 0 make head-on collisions, and these are most important for slow electrons and weak fields. For strong fields and fast particles, the main contribution to the scattering may come from large values of l , when the calculation of scattered intensities by this method is not so convenient. In these cases the Born approximation is usually satisfactory. The agreement between Holtsmark’s calculations and experiment is reasonably good, showing that the distortion of the wave is of fundamental importance in the scattering of slow electrons.

Absolute inner-shell cross section determination for EELS analysis

1988 ◽  
Vol 46 ◽  
pp. 534-535
Author(s):  
P.A. Crozier
Keyword(s):  
Cross Section ◽  
Cross Sections ◽  
Absolute Cross Section ◽  
Specimen Thickness ◽  
Mass Thickness ◽  
Scattering Cross ◽  
Before And After ◽  
Estimated Error ◽  
Scattering Cross Sections ◽  
Electron Microscopist

Absolute inelastic scattering cross sections or mean free paths are often used in EELS analysis for determining elemental concentrations and specimen thickness. In most instances, theoretical values must be used because there have been few attempts to determine experimental scattering cross sections from solids under the conditions of interest to electron microscopist. In addition to providing data for spectral quantitation, absolute cross section measurements yields useful information on many of the approximations which are frequently involved in EELS analysis procedures. In this paper, experimental cross sections are presented for some inner-shell edges of Al, Cu, Ag and Au.Uniform thin films of the previously mentioned materials were prepared by vacuum evaporation onto microscope cover slips. The cover slips were weighed before and after evaporation to determine the mass thickness of the films. The estimated error in this method of determining mass thickness was ±7 x 107g/cm2. The films were floated off in water and mounted on Cu grids.

scholarly journals Towards fully nonperturbative computations of inelastic ℓN scattering cross sections from lattice QCD

2020 ◽  
Vol 102 (11) ◽  
Author(s):  
Hidenori Fukaya ◽  
Shoji Hashimoto ◽  
Takashi Kaneko ◽  
Hiroshi Ohki
Keyword(s):  
Lattice Qcd ◽  
Cross Sections ◽  
Scattering Cross ◽  
Scattering Cross Sections

scholarly journals Combining ADF-EDX scattering cross-sections for elemental quantification of nanostructures

2021 ◽  
Vol 27 (S1) ◽  
pp. 600-602
Author(s):  
Zezhong Zhang ◽  
Annick De Backer ◽  
Ivan Lobato ◽  
Sandra Van Aert ◽  
Peter Nellist
Keyword(s):  
Cross Sections ◽  
Scattering Cross ◽  
Scattering Cross Sections

scholarly journals Core-Shell Nano-Antenna Configurations for Array Formation with More Stability Having Conventional and Non-Conventional Directivity and Propagation Behavior

Nanomaterials ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 99
Author(s):  
Qaisar Hayat ◽  
Junping Geng ◽  
Xianling Liang ◽  
Ronghong Jin ◽  
Sami Ur Rehman ◽  
...  
Keyword(s):  
Plane Wave ◽  
Propagation Direction ◽  
Core Shell ◽  
Incident Plane Wave ◽  
Polarization Direction ◽  
Shell Nanoparticles ◽  
Incident Plane ◽  
Core Shell Nanoparticles ◽  
Coated Nanoparticle ◽  
2D Array

The enhancement of optical characteristics at optical frequencies deviates with the choice of the arrangement of core-shell nanoparticles and their environment. Likewise, the arrangements of core-shell nanoparticles in the air over a substrate or in liquid solution makes them unstable in the atmosphere. This article suggests designing a configuration of an active spherical coated nanoparticle antenna and its extended array in the presence of a passive dielectric, which is proposed to be extendable to construct larger arrays. The issue of instability in the core-shell nanoantenna array models is solved here by inserting the passive dielectric. In addition to this, the inclusion of a dielectric in the array model reports a different directivity behaviour than the conventional array models. We found at first that the combination model of the active coated nanoparticle and passive sphere at the resonant frequency can excite a stronger field with a rotated polarization direction and a propagation direction different from the incident plane-wave. Furthermore, the extended 2D array also rotates the polarization direction and propagation direction for the vertical incident plane-wave. The radiation beam operates strong multipoles in the 2D array plane at resonant frequency (behaving non-conventionally). Nevertheless, it forms a clear main beam in the incident direction when it deviates from the resonance frequency (behaving conventionally). The proposed array model may have possible applications in nano-amplifiers, nano-sensors and other integrated optics.

Sign in / Sign up

Export Citation Format

Share Document