Plasma charge force near the dust particles chain levitated in a gas-discharge

Abstract

In the current paper a numerical study of the forces acting of a one-dimensional chain of three dust particles levitating in the near-electrode layer of a gas discharge plasma is presented. In the described model dust particle motion is calculated in consideration of the action of gravity, external electric field, the Coulomb repulsion and the force induced by plasma space charge. The dependences of the dust particles charges and their position in space on the mean value of external electric field were calculated. The investigation showed the effect of discharging dust particles in the chain due to ion focusing. The spatial distribution of forces acting on the dust particle chain has been studied. It is noted that the Coulomb repulsion force relative to the center of the chain loses its symmetry with an increase in the mean electrostatic field. It is shown that the displacement of a chain of dust particles is determined by the force induced by the plasma space charge.