Internal acoustic gravity waves.
Dispersion relation of internal acoustic gravity wave motion in compressible nonviscous and nonheatconducting atmosphere
Mclellan, A., IV↗
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Propagation in ferrite-filled coaxial transmission lines.
Dispersion relations for propagation of quasi-TEM mode and higher order symmetric modes in longitudinally magnetized ferrite filled coaxial waveguide
Mueller, R. S.↗
Surface plasmons in thin films.
Dispersion relations for surface plasma oscillations in normal metals for single and multiple films taking into account retardation effects, noting dielectric function
Economou, E. N.↗
A guiding centre Vlasov equation and its application to Alfven waves.
Guiding center Vlasov equation derived dielectric tensor of collisionless plasma, obtaining dispersion relation of Alfven waves in warm plasma
Fejer, J. A.↗
Propagation of low-frequency electrostatic waves in a magnetic field
LF electrostatic waves oblique to magnetic field in plasma, evaluating dispersion relation near ion cyclotron frequency
Dory, R. A.↗
Propagation of acoustic-gravity waves in a turbulent atmosphere
Atmospheric turbulence effects on acoustic-gravity waves propagation, deriving dispersion relation for phase velocity and propagation constants
Liu, C. H.↗
A continuum theory for an elastic solid with elastic micro-inclusions
Elastic particulate composite solid with microinclusions, deriving dispersion relations governing plane longitudinal wave propagation modes by analogy with continuum theory
Habip, L. M.↗
Trapped low frequency waves propagating along a warm plasma cylinder
Trapped LF ion wave propagation along warm plasma cylinder imbedded in dielectric, obtaining dispersion relation
Klevans, E. H.↗
Electrothermal oscillations and the quasilinear theory of electron enthalpy fluctuations in magnetohydrodynamic generators and magnetoplasmadynamic arc thrusters
Flucturations in electron density and temperature coupled through OHM's Law are studied for MHD power generator and MPD arc thruster applications. The dispersion relation based on linear theory is derived, and the two limiting cases of infinite ionization rate and frozen flow are examined. The nonlinear effects of the frozen flow case are then studied in the quasilinear limit. Equations are derived for the amplitude of the fluctuation and its effect upon Ohm's Law and the electron temperature equation. Conditions under which a steady state can exist in the presence of the fluctuation are examined, and effective transport properties are determined.
Smith, J. M.↗
A resonant instability of model proton radiation belts in the Jovian magnetosphere
The ion cyclotron instability and characteristics of the ion cyclotron wave are discussed. A mathematical perturbation technique is applied to the dispersion relations, and the results are applied to the case of propagation parallel to the magnetic field. The ion cyclotron wave is determined in its damping and growth characteristics by resonant protons and electrons, found in momentum space on resonant surfaces. In the relativistic case the resonant surfaces are hyperbolas of revolution around the magnetic field, and protons can have a stabilizing effect. Instability rates are calculated for the region in the equatorial plane with the Ioannidis and Brice density model. The upper limit of proton flux which gives an energy density of the same order of magnitude as the magnetic field energy density is obtained. The upper limit is plotted with respect to distance from Jupiter and the minimum resonant energy contributing to the instability is also plotted.
Neubauer, F. M.↗
Waves along a cylindrical 'grid-like' antenna in an anisotropic compressible plasma.
The dispersion equation is obtained analytically of waves along an infinitely long cylindrical ?grid-like' antenna in an anisotropic compressible homogeneous plasma. Numerical solutions of this equation show that an external static magnetic field has great influence upon the anomalously dispersive region of the dispersion relation around the plasma frequency.
Yu, W.↗
Longitudinal waves in a perpendicular collisionless plasma shock. III.
This paper considers electrostatic waves in a Vlasov plasma of unmagnetized ions and magnetized electrons undergoing an E x B drift. The linear dispersion relation is solved numerically for an electron temperature approximately equal to the ion temperature. For a fixed ratio of drift velocity to electron thermal velocity, the growth rates of the E x B electron drift instability are smaller, and the waves are stabilized at much smaller values of k.B than in the case where electron temperature is much larger than the ion temperature.
Gary, S. P.↗
Numerical solution for propagation of coupled longitudinal and transverse waves normal to the applied magnetic field in a three-fluid medium.
The solution was obtained without approximating the dispersion relation. This was made possible by the use of a computer method for carrying out the extremely large number of algebraic manipulations involved. The three-fluid model employed accounts for the interaction of the electron, ion, and neutral species. The solution for the e-folding distance describes the damping characteristics of each wave mode. Each of the e-folding solutions corresponds to one of the phase velocity solutions.
Mcclendon, R. W.↗
Stability of a steady, large amplitude whistler wave.
Study of the behavior of weak electrostatic waves in a collisionless magnetoplasma supporting a steady large amplitude whistler wave. All waves are assumed to propagate parallel to a uniform background magnetic field B sub zero. In the presence of the whistler wave fields each particle executes an oscillatory motion parallel to B sub zero, in addition to a translation along B sub zero and transverse motions. This oscillation causes the Landau resonance to be replaced by a series of new resonances between particles and the electrostatic modes. A distribution function for the perturbed plasma is constructed by solving the Vlasov equation, linearized in the electrostatic wave amplitudes. A dispersion relation is obtained and solved approximately for the growth/damping rate of the perturbations. Growing electrostatic modes are found to be approximately uncoupled. Trapped particles have a strong influence on the stability of the system.
Palmadesso, P. J.↗
Ion acoustic waves in a multi-ion plasma.
An exact treatment of the multispecies ion acoustic dispersion relation is given for an argon/helium plasma. Phase velocity and damping are obtained as a function of ion-electron temperature ratio and relative densities of the two species. There are two important modes in the plasma, with quite different phase velocities, which are referred to as principal heavy ion mode and principal light ion mode. Which of these is dominant depends on the relative densities of the two components, but, in general, the light ion mode becomes important for surprisingly small light ion contamination. Approximate analytic expressions are derived from damping rates and phase velocities and their domains of validity are investigated. Relevance of the results for the investigation of collisionless shocks is discussed.
Fried, B. D.↗
The inverse scattering problem at fixed angular momentum for nonlocal separable interactions
The problem of inverse scattering at fixed angular momentum is considered. The problem is particularized to the case of nonlocal separable interactions. A brief survey of the inverse problem for nonlocal separable interactions is presented. This problem can be solved exactly by integration. It amounts to solving singular integral equations of the Hilbert-Mushkhelishvili type, which have been studied extensively in the past and appear in many areas of physics, including theory of elasticity and dispersions relations in high energy physics.
Chadan, K.↗
Low-frequency macroscopic instabilities of fully ionized magnetoplasma
Studies are described of low-frequency quasi-static instabilities in a fully ionized plasma. The plasma is assumed to be immersed in a uniform magnetic field, and is either uniform or has a number density gradient perpendicular to the magnetic field. A moment equation description of the ion and electron dynamics is used; collisions are assumed to have a strong effect on electron motion along the magnetic field. Before considering specific modes, a stability analysis is developed which allows a classification of wave growth characteristics to be made for a bounded system from solutions to the dispersion relation for an infinite system. Also, a method is given for calculating the normal mode frequencies and wave profiles by using the reflection coefficients at the boundaries. For wave propagation perpendicular to the magnetic field, the flute wave is studied in cylindrical geometry. The destabilizing effect of a radial electric field is considered by solving a differential equation.
Rognlien, T. D.↗
Lagrangian description of warm plasmas
Efforts are described to extend the averaged Lagrangian method of describing small signal wave propagation and nonlinear wave interaction, developed by earlier workers for cold plasmas, to the more general conditions of warm collisionless plasmas, and to demonstrate particularly the effectiveness of the method in analyzing wave-wave interactions. The theory is developed for both the microscopic description and the hydrodynamic approximation to plasma behavior. First, a microscopic Lagrangian is formulated rigorously, and expanded in terms of perturbations about equilibrium. Two methods are then described for deriving a hydrodynamic Lagrangian. In the first of these, the Lagrangian is obtained by velocity integration of the exact microscopic Lagrangian. In the second, the expanded hydrodynamic Lagrangian is obtained directly from the expanded microscopic Lagrangian. As applications of the microscopic Lagrangian, the small-signal dispersion relations and the coupled mode equations are derived for all possible waves in a warm infinite, weakly inhomogeneous magnetoplasma, and their interactions are examined.
Kim, H.↗