Transition Radiation from a Plasma Boundary

1972 ◽  
Vol 50 (19) ◽  
pp. 2244-2252 ◽  
Author(s):  
S. R. Seshadri
Keyword(s):  
Surface Wave ◽  
Resonant Frequency ◽  
Half Space ◽  
Particle Velocity ◽  
Free Space ◽  
Point Charge ◽  
Transition Radiation ◽  
Plasma Boundary ◽  
Wave Power ◽  
Space Wave

The transition radiation emitted by a point charge moving with a uniform velocity across a plane interface separating a half-space of plasma from another half-space of free space is investigated. The transition radiation is partly in the form of space waves and partly in the form of surface waves. The characteristics of these waves are discussed with the help of some typical numerical results. The surface-wave power is shown to be many orders larger than the space-wave power and near the surface-wave resonant frequency an increase in the particle velocity is found to decrease the surface-wave power.

SURFACE WAVES ALONG AN AXIALLY MAGNETIZED PLASMA COLUMN: I. SYMMETRIC MODES

1967 ◽  
Vol 45 (9) ◽  
pp. 2889-2911 ◽  
Author(s):  
G. L. Yip ◽  
S. R. Seshadri
Keyword(s):  
Magnetic Field ◽  
Surface Wave ◽  
Resonant Frequency ◽  
Surface Waves ◽  
Infinite Number ◽  
Applied Magnetic Field ◽  
Cold Plasma ◽  
Magnetized Plasma ◽  
Wave Power ◽  
Point Electric Dipole

The characteristics of surface waves excited by an axially oriented point electric dipole situated along the axis of an infinitely long; and axially magnetized column of uniform cold plasma are investigated. The surface waves are found to be slow waves and exist only below the upper hybrid resonant frequency. In the gyromagnetic and plasma resonance regions, the existence of an infinite number of discrete modes is noted. The dispersion curves are presented for different values of the strength of the applied magnetic field and the column radius. Also, the power transported by the surface waves is evaluated and is found to become infinite in the two resonance frequency regions. A technique for the removal of this singularity in the surface wave power is indicated.

FIELD OF A LINE SOURCE SITUATED PARALLEL TO A SURFACE-WAVE STRUCTURE COMPRISING A PAIR OF UNIDIRECTIONALLY CONDUCTING SCREENS

1967 ◽  
Vol 45 (6) ◽  
pp. 2145-2172 ◽  
Author(s):  
R. K. Arora
Keyword(s):  
Surface Wave ◽  
Integral Representation ◽  
Radiation Field ◽  
Half Space ◽  
Line Source ◽  
Wave Structure ◽  
Wave Power ◽  
Lower Half Space ◽  
Electric Line ◽  
Wave Modes

The problem of radiation from an electric line source situated parallel to a surface-wave structure composed of a pair of parallel unidirectionally conducting screens is considered. The screens are conducting in directions making angles α and — α, respectively, with the x axis, while the line source is directed parallel to the γ axis and is located either above or between the two screens. The problem is resolved as the superposition of symmetrical and antisymmetrical sources, since either of the two surface-wave modes that can be supported on the structure is associated with an appropriate type of excitation. Both surface-wave modes are excited in the superposed case of a line source.The radiation field is evaluated and, under suitable conditions, is seen to exhibit sharp peaks. The correspondence of these peaks with complex poles in the integral representation of the field is demonstrated. It is further observed that, when the line source is situated above the structure, the amplitude of the field components in the lower half-space is independent of the location of the source, although the phase is affected. The surface-wave power is determined and it is shown that high values of launching efficiency are readily attainable.

Guided Surface Waves on an Elastic Half Space

1971 ◽  
Vol 38 (4) ◽  
pp. 899-905 ◽  
Author(s):  
L. B. Freund
Keyword(s):  
Wave Propagation ◽  
Surface Wave ◽  
Surface Waves ◽  
Half Space ◽  
Body Wave ◽  
Three Dimensional ◽  
Elastic Half Space ◽  
Normal Displacement ◽  
Rigid Barrier ◽  
Wave Disturbances

Three-dimensional wave propagation in an elastic half space is considered. The half space is traction free on half its boundary, while the remaining part of the boundary is free of shear traction and is constrained against normal displacement by a smooth, rigid barrier. A time-harmonic surface wave, traveling on the traction free part of the surface, is obliquely incident on the edge of the barrier. The amplitude and the phase of the resulting reflected surface wave are determined by means of Laplace transform methods and the Wiener-Hopf technique. Wave propagation in an elastic half space in contact with two rigid, smooth barriers is then considered. The barriers are arranged so that a strip on the surface of uniform width is traction free, which forms a wave guide for surface waves. Results of the surface wave reflection problem are then used to geometrically construct dispersion relations for the propagation of unattenuated guided surface waves in the guiding structure. The rate of decay of body wave disturbances, localized near the edges of the guide, is discussed.

The Piezoelectric and Piezomagnetic Effects on the Surface Wave Speed

2012 ◽  
Vol 268-270 ◽  
pp. 1619-1622 ◽  
Author(s):  
Li Li ◽  
Yi Wen Wei ◽  
P.J. Wei
Keyword(s):  
Surface Wave ◽  
Half Space ◽  
Wave Speed ◽  
Open Circuit ◽  
Numerical Examples ◽  
Piezomagnetic Effects

the piezoelectric and piezomagnetic effects and the influence of short and open circuit on the surface wave speed are investigated in this paper. First, the elastic, piezoelectric and piezomagnetic coefficients in the considered ordinate system are obtained by Bonde transformation from that in the crystal axes ordinate system. Then, the equation which surface wave speed satisfies is derived from the free traction condition on the surface of piezoelectric and piezomagnetic half space with consideration of short and open circuit case. Some numerical examples are given and the piezoelectric and piezomagnetic effects and the influence of short and open circuit on the surface wave speed are shown graphically.

scholarly journals DEVELOPMENT OF WAVE POWER GENERATION SYSTEM SUITABLE FOR INNER BAY

2020 ◽  
pp. 39
Author(s):  
Rioko Hirota ◽  
Takaaki Shigematsu ◽  
Kenji Katoh ◽  
Tatsuro Wakimoto ◽  
Shinya Yoshioka
Keyword(s):  
Power Generation ◽  
Particle Velocity ◽  
High Energy ◽  
Wave Power ◽  
Generation System ◽  
Water Particle ◽  
Water Turbine ◽  
Power Generation System ◽  
The Relationship ◽  
Wave Power Generation

With the increasing demand for renewable energy in the world, research contributing to the improvement of the technology level of wave power generation is essential. The authors have been developed a wave power generation system using port facilities in inner bays with high energy-consuming cities. In this study, the relationship between the rotational characteristics of a Savonius water turbine and the water particle velocity was quantitatively evaluated under the calm conditions of the inner bay, such as wave motion, flow, and coexistence of wave and current. According to the experimental results, it is found that the relationship between the rotational circumferential speed and the water particle velocity of the water turbine installed in a wave field tends to be different from that in a flow field and is evaluated by different equations. In addition, the relationship between circumferential velocity and the water particle velocity has also been formulated when installed in a wave-current coexistence field.Recorded Presentation from the vICCE (YouTube Link): https://youtu.be/KX0XBFuao48

Determination of the velocity of short electromagnetic waves by interferometry

1952 ◽  
Vol 213 (1112) ◽  
pp. 123-141 ◽  
Keyword(s):  
Phase Velocity ◽  
Electromagnetic Radiation ◽  
Free Space ◽  
Electromagnetic Waves ◽  
Wave Beam ◽  
Wave Length ◽  
Wave Frequency ◽  
Space Wave

A new measurement of the velocity of electromagnetic radiation is described. The result has been obtained, using micro-waves at a frequency of 24005 Mc/s ( λ = 1∙25 cm), with a form of interferometer which enables the free-space wave-length to be evaluated. Since the micro-wave frequency can also be ascertained, phase velocity is calculated from the product of frequency and wave-length. The most important aspect of the experiment is the application to the measured wave-length of a correction which arises from diffraction of the micro-wave beam. This correction is new to interferometry and is discussed in detail. The result obtained for the velocity, reduced to vacuum conditions, is c 0 = 299792∙6 ± 0∙7 km/s.

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