Nonlinear Dust Ion Acoustic Waves Research Articles

Effects of trapped electron temperature, dust charge variations, and grain radius on the existence of the dust-ion-acoustic waves

The ionization source model is considered to study the effects of trapped electron temperature, dust charge variations, and grain radius on the nonlinear dust ion acoustic waves (DIAWs) in dusty plasmas having trapped electrons. It has been shown that the nonlinear DIAWs damp waves and these waves are governed by a damped modified Korteweg–de Vries equation. It is found that only compressive dust ion acoustic solitons can propagate in dusty plasmas with trapped electrons. The amplitude and the width of the solitons depend mainly on the trapped electron temperature, dust charge variations and grain radius. The existence of the solitons is independent of the trapped electron temperature. The findings of this investigation may be useful in understanding laboratory plasma phenomena and astrophysical situations.

The role of dust charge fluctuations on nonlinear dust ion-acoustic waves

The nonlinear propagation of the dust ion-acoustic waves has been investigated accounting for the charge fluctuation dynamics of stationary dust grains in an unmagnetized dusty plasma. The Korteweg-de Vries equation, as well as the Korteweg-de Vries-Burgers equation, are derived by employing the reductive perturbation method. It has been shown that dust charge fluctuations produce a dissipation which is responsible for shock waves. Conditions for the formation of dust ion-acoustic solitary and shock waves as well as their properties are clearly explained. The implications of our investigations to both space and laboratory dusty plasmas are discussed.

Collisionless damping of nonlinear dust ion acoustic wave due to dust charge fluctuation.

A dissipation mechanism for the damping of the nonlinear dust ion acoustic wave in a collisionless dusty plasma consisting of nonthermal electrons, ions, and variable charge dust grains has been investigated. It is shown that the collisionless damping due to dust charge fluctuation causes the nonlinear dust ion acoustic wave propagation to be described by the damped Korteweg-de Vries equation. Due to the presence of nonthermal electrons, the dust ion acoustic wave admits both positive and negative potential and it suffers less damping than the dust acoustic wave, which admits only negative potential.

Ion acoustic shock waves in a collisional dusty plasma

The effect of ion–dust collisions on small amplitude nonlinear dust ion acoustic waves has been investigated. Analytical investigation shows that propagation of the small amplitude wave is governed by Korteweg–de Vries (KdV) Burger equation. It is found that the coefficient of the Burger term is proportional to the ion viscosity, which arises through ion–dust collisions and depends on the temperatures and number densities of the electrons, ions and also on the number density of dust grains, as seen in a recent experiment (Nakamura et al.). Numerical investigations on the basis of that experimental data show that the dust–ion acoustic wave exhibits both oscillatory and monotonic shocks depending on the number density of dust particles, as observed in that experiment [Nakamura et al., Phys. Rev. Lett. 83, 1602 (1999)].

Small Amplitude Nonlinear Dust Ion Acoustic Waves in a Magnetized Dusty Plasma With Charge Fluctuation

A theoretical investigation of one dimensional dynamics of nonlinear electrostatic dust ion acoustic waves in a magnetized dusty plasma has been made by reductive perturbation technique. The effects of both the adiabatic and the nonadiabatic dust charge variation are incorporated. The most interesting feature is that the nonlinear evolution equation of the dust ion acoustic wave for nonadiabatic dust charge variation is the Korteweg-de Vries (KdV) Burger equation, whereas for adiabatic dust charge variation, the equation is the KdV equation. A nonadiabaticity generated anomalous dissipative effect causes generation of dust ion acoustic shock waves, a new mechanism for the generation of shock waves. Numerical integration of the KdV Burger equation shows that dust ion acoustic waves admit oscillatory (dispersion dominant) or monotone (dissipation dominant) shock solutions. It is also seen that the magnetic field and the dust charge variations significantly modify the wave amplitude.

Dust ion acoustic shock waves in a collisionless dusty plasma

The effects of nonadiabatic dust charge variation on nonlinear dust ion acoustic waves in collisionless dusty plasma have been studied. Nonadiabaticity generated dissipative effect is found to cause generation of dust ion acoustic shock wave governed by the Korteweg–de Vries (KdV) Burger equation. Numerical integration of KdV Burger equation shows that it has either oscillatory (dispersion dominant case) or quasi-monotone (dissipation dominant case) shock wave solutions.

Dust ion acoustic shock waves in a collisionless dusty plasma

The effects of nonadiabatic dust charge variation on nonlinear dust ion acoustic waves in collisionless dusty plasma have been studied. Non adiabaticity generated dissipative effect is found to cause generation of dust ion acoustic shock wave governed by the Korteweg–de Vries (KdV) Burger equation. Numerical integration of KdV Burger equation shows that it has either oscillatory (dispersion dominant case) or quasi-monotone (dissipation dominant case) shock wave solutions.

Nonlinear properties of small amplitude dust ion acoustic solitary waves

In this paper some nonlinear characteristics of small amplitude dust ion acoustic solitary wave in three component dusty plasma consisting of electrons, ions, and dust grains have been studied. Simultaneously, the charge fluctuation dynamics of the dust grains under the assumption that the dust charging time scale is much smaller than the dust hydrodynamic time scale has been considered here. The ion dust collision has also been incorporated. It has been seen that a damped Korteweg–de Vries (KdV) equation governs the nonlinear dust ion acoustic wave. The damping arises due to ion dust collision, under the assumption that the ion hydrodynamical time scale is much smaller than that of the ion dust collision. Numerical investigations reveal that the dust ion acoustic wave admits only a positive potential, i.e., compressive soliton.

Observation of Ion-Acoustic Shocks in a Dusty Plasma

Linear and nonlinear dust ion-acoustic waves are studied experimentally in a homogeneous unmagnetized dusty plasma. In the linear regime, the phase velocity of the wave increases and the wave suffers heavy damping with increasing dust density. An oscillatory ion-acoustic shock wave in usual Ar plasma transforms into a monotonic shock front when it travels through the dusty plasma column. The Korteweg--de Vries--Burgers equation is numerically integrated taking experimental parameters into account, and the results are compared with the experimental findings.