Convective dust clouds in a complex plasma

TL;DR

This study investigates the formation and behavior of convective dust clouds in a complex plasma within a glow discharge, highlighting how thermal creep-induced gas motion influences dust convection.

Contribution

It demonstrates the impact of thermal creep-driven gas flow on dust cloud convection in a plasma, providing detailed analysis of cloud shape, velocity, and acting forces.

Findings

Dust clouds form near the tube center with counter-rotation.

Convection is driven by gas motion caused by thermal creep.

Forces on particles are quantitatively analyzed.

Abstract

The plasma is generated in a low frequency glow discharge within an elongated glass tube oriented vertically. The dust particles added to the plasma are confined above the heater and form counter-rotating clouds close to the tube centre. The shape of the clouds and the velocity field of the conveying dust particles are determined. The forces acting on the particles are calculated. It is shown that convection of the dust is affected by the convective gas motion which is triggered, in turn, by thermal creep of the gas along the inhomogeneously heated walls of the tube.