Investigating transport of dust particles in plasmas

TL;DR

This paper presents an algorithm for automatic extraction of dust particle trajectories in plasma images, enabling statistical analysis of dust dynamics and their impact on plasma properties, with results from a RF reactor showing different behaviors at various time scales.

Contribution

Introduces a new algorithm for automatic particle trajectory extraction and applies R/S analysis to study dust dynamics in plasma.

Findings

Short-term dust motion dominated by collisions

Long-term behavior influenced by plasma fluctuations

Decomposition of dust dynamics across different time scales

Abstract

An algorithm has been developped, which makes it possible to automatically extract trajectories of a large number of particles from fast imaging data, allowing a statistical analysis of particles trajectories under various plasma conditions, a better understanding of their influence on plasma properties, and a better characterization of the plasma itself. In this contribution, we focus on results obtained in a radiofrequency parallel plate reactor, where a large amount of micron-sized carbon dust is produced in situ. The use of the rescaled range analysis (R/S analysis) applied to dust particles displacements allows decomposing dust dynamic on different time scales. It is shown that dust displacement is dominated by collisions on short time scales whereas long term behaviour is strongly influenced by large scale plasma fluctuations.