Characteristics of ion-acoustic solitary wave in a laboratory dusty plasma under the influence of ion-beam

TL;DR

This study investigates how ion beams and charged dust impurities affect the propagation and characteristics of dust ion-acoustic solitary waves in a laboratory plasma, revealing mode bifurcation, critical velocities, and dust influence on wave properties.

Contribution

It provides experimental insights into the effects of ion beams and dust impurities on solitary wave behavior, including mode bifurcation and velocity modifications, aligning with theoretical models.

Findings

Ion beam causes bifurcation into fast and slow modes.

Charged dust reduces critical beam velocity and modifies phase velocity.

Experimental results agree with theoretical K-dV predictions.

Abstract

We study the influence of ion beam and charged dust impurity on the propagation of dust ion-acoustic (DIA) solitary wave (SW) in an unmagnetized plasma consisting of Boltzmann distributed electrons, positive ions, positive ion beam and negatively charged immobile dusts in a double plasma device. On interacting with an ion beam, the solitary wave is bifurcated into a compressive fast and a rarefactive slow beam mode, and appears along with the primary wave. However, there exists a critical velocity of the beam beyond which the amplitude of the fast solitary wave starts diminishing and rarefactive slow beam mode propagates with growing amplitude. Whereas, the presence of charged dust impurity in the plasma reduces this critical beam velocity and a substantial modification in the phase velocity of the slow beam mode is observed with increasing dust density. Furthermore, the nonlinear wave velocity (Mach number) as well as the width of the compressive solitons are measured for different beam velocity and dust density, and are compared with those obtained from the K-dV equation. The experimental results are found in a well agreement with the theoretical predictions.