Publications

Structure of the ion wakefield in dusty plasmas

Hebner, Gregory A.; Riley, M.E.

The magnitude and structure of the attractive ion wakefield potential below a negatively charged dust particle levitated in the plasma sheath region was measured as a function of the interparticle spacing. The ion wakefield force field generated by an upper lighter target dust particle was determined by colliding it with a heavier probe dust particle levitated at a lower height. The interaction potentials were obtained from the particle's position and velocity by numerically inverting the Newtonian equations of motion. A transition from repulsive, nonvertically aligned pairs, to attractive vertically aligned pairs, and then back to nonvertically aligned pairs, was observed as the vertical spacing between the particles was increased.