Numerical study of anisotropic potential distribution near dust chains in the Plasmakristall-4 dusty plasma*

Dust particles in the Plasmakristall-4 (PK-4) facility on board the International Space Station have been found to form extended filaments in the presence of an external polarity-switched DC electric field. These filaments are aligned in the direction of the externally applied electric field. In the direction parallel to the electric field, the dust particles are strongly coupled and behave as a crystalline-like structure. On the other hand, there is a weaker coupling among particles in the direction across filaments (i.e. perpendicular to the electric field). Due to the presence of dust particles, the charge distribution in a plasma is modified, as well as the spatial distribution of the potential. This gives rise to regions of positive and negative potential which depend on the interparticle distance, plasma pressure, dust and ion densities and other properties. The anisotropic potential distribution observed in these dusty plasmas can be compared to numerical simulations to understand anisotropies in the interparticle interaction potentials in these systems. In this project we aim to obtain a model of the electric potential distribution which captures the effects of the anisotropic ion wakes derived from an N-body numerical simulation of the dust and ions for time-averaged and time-varying plasma conditions.