Examining the Electric Potential Near Self-Organized Dust Structures*

It has been previously shown that a negatively charged dust grain immersed in a flowing plasma leads to the formation of a positively charged ion wake downstream from the dust.  The presence of these ion wakes mediates the non-reciprocal interaction between dust grains and can result in many interesting collective behaviors.  Dust grains have been observed in certain experimental conditions to form long single chains of particles.  By manipulating the experimental conditions, the dust chain can be forced to undergo a reversible transition into other stable configurations such as the zig-zag and helical structures.  An accurate description of the electric potential near the location of the dust structures is necessary to be able to model the motions of charged dust and ions realistically.  Here we present an analysis of the electric potential near stable configurations of charged dust obtained from the results from a molecular dynamics simulation of the ion and dust motion and dust charging.