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The effects of a cold ion beam on an ion-acoustic solitary wave whose potential is large enough to reflect the ion beam are studied in the regime in which the solitary-wave response to the beam is adiabatic. It is shown that the solitary wave can be amplified by a large factor, and that it is accelerated until its velocity equals the beam velocity. [ABSTRACT FROM AUTHOR]

The properties of solitary waves in a plasma with an ion beam are investigated. The two conditions for the existence of solitary-wave solutions are determined and presented graphically in parameter space. Electron inertia is shown to restrict the regime of the fast and slow beam solitary waves to beam velocities that are less than the electron thermal velocity. [ABSTRACT FROM AUTHOR]

The properties of arbitrary-amplitude solitary waves in a plasma consisting of drifting ions and nondrifting electrons are investigated. The conditions for the existence of solitary-wave solutions are determined. It is shown that electron inertia has the significant effect of restricting the regime of solitary waves to ion drift velocities that are less than the electron thermal speed. Because of this restriction relativistic effects are small. [ABSTRACT FROM AUTHOR]

For a weakly nonuniform medium, a solitary wave solution of the variable-coefficient nonlinear Schrödinger equation is obtained through second order in the expansion parameter. From a generalization of the second-order result, the form of the solution to all orders is derived from which the conditions for an exact, distortionless solitary wave in a nonuniform medium are obtained. By use of a transformation, these results are shown to apply a weakly dissipative medium. [ABSTRACT FROM AUTHOR]

The soliton modifications resulting from the addition of a small third derivative term, due to higher-order dispersion, to the nonlinear Schrödinger equation are investigated. Based on direct perturbation theory, it is shown that through first order, the soliton phase and velocity are modified, but the shape, amplitude, and width are unchanged. The radiation stimulated by the third derivative term, which is not predicted by the perturbation theory, is also derived. The expression obtained confirms the result of Wai (Ph.D. thesis, University of Maryland, 1988), which was obtained by a different method. The rate of change of the soliton amplitude due to this radiation, which emerges in front of the soliton, is calculated. The nonlinear term that drives the radiation is shown to grow to a value that is much larger than the unperturbed value. [ABSTRACT FROM AUTHOR]

The reflection of a planar ion-acoustic soliton from an insulated or a biased metallic planar wall is studied. Numerical solutions of the cold-ion fluid equations, the Boltzmann distribution for electrons, and Poisson's equation show that the incident soliton is partially reflected and partially absorbed by the wall. The reflection is larger for wider solitons and for a more negatively biased wall. The numerical results are in reasonable agreement with the recent experiment of Nishida [Phys. Fluids 27, 2176 (1984) ]. [ABSTRACT FROM AUTHOR]

The properties of an ion-acoustic soliton in a weakly inhomogeneous plasma are studied. Unlike previous analyses, the soliton amplitude is not required to be small. The ion generation rate is assumed to be either proportional to the electron density or to be uniform. Assuming that the local soliton width is small compared with the scale length of the plasma inhomogeneity, a perturbation theory is developed which gives the local speed and amplitude of the soliton. For a small amplitude soliton, simple expressions for the local soliton speed, peak soliton potential, and peak soliton ion density are derived. It is shown that both the soliton velocity relative to the ion drift velocity and the peak soliton potential do not vary greatly as the soliton moves from the plasma center toward the sheath. The peak ion density, however, varies over a wider range. These results are shown to agree with those from direct numerical integration of the basic equations. [ABSTRACT FROM AUTHOR]

Features numerical solutions of two colliding electromagnetic solitary waves in a plasma. Properties of one-dimensional, weakly nonlinear electromagnetic solitary waves in a plasma; Modified shapes of the waves; Production of a trailing wake of plasma oscillations by the collision.

Some properties of small-amplitude ion-acoustic solitons in a plasma consisting of nondrifting electrons and drifting ions are investigated. Electron inertia effects are shown to be considerably more important than relativistic effects. It is also shown that ion-acoustic soliton solutions exist only if the ion drift velocity is less than the electron thermal velocity. [ABSTRACT FROM AUTHOR]