Ion-acoustic solitary waves and shocks in a collisional dusty negative ion plasma

TL;DR

This paper investigates how ion-dust collisions and viscosity influence ion-acoustic waves and shocks in a negative ion plasma with dust, deriving a modified KdV-Burgers equation to describe small amplitude solitary waves and shocks.

Contribution

It introduces a modified KdV-Burgers equation for small amplitude SWS in collisional negative ion plasmas with dust, analyzing the effects of dust charge and collisions.

Findings

Negative ion plasmas with positively charged dust support negative potential SWS.

Both positive and negative potential perturbations can exist with negatively charged dust.

Profiles of solitary waves and shocks are numerically examined for laboratory and space plasma parameters.

Abstract

We study the effects of ion-dust collisions and ion kinematic viscosities on the linear ion-acoustic instability as well as the nonlinear propagation of small amplitude solitary waves and shocks (SWS) in a negative ion plasma with immobile charged dusts. {The existence of two linear ion modes, namely the `fast' and `slow' waves is shown, and their properties are analyzed in the collisional negative ion plasma.} {Using the standard reductive perturbation technique, we derive a modified Korteweg-de Vries-Burger (KdVB) equation which describes the evolution of small amplitude SWS.} {The profiles of the latter are numerically examined with parameters relevant for laboratory and space plasmas where charged dusts may be positively or negatively charged.} It is found that negative ion plasmas containing positively charged dusts support the propagation of SWS with negative potential. However, the perturbations with both positive and negative potentials may exist when dusts are negatively charged. The results may be useful for the excitation of SWS in laboratory negative ion plasmas as well as for observation in space plasmas where charged dusts may be positively or negatively charged.