Employing dust particle chains as a wakefield diagnostic

Dust particles often form vertical chains due to the influence of the wakefield produced by streaming ions in the plasma sheath produced within an experimental dusty plasma. These particle chains are proving to be a unique diagnostic tool for investigating the physics behind the basic properties of the ion wakefield in the plasma sheath. In this paper, an experimental method is presented for investigating the wakefield employing a new oscillation technique designed to perturb a two-particle vertical chain. Damped attenuated oscillations are generated via an external dc bias on the lower electrode. A fast Fourier transform is used to produce a spectrum of the oscillation data collected, and a center of mass oscillation is identified.