Instability of plasma-dust systems with a macroparticle charge gradient

An analysis is made of various self-oscillations which appear in plasma-dust systems with spatially varying macroparticle charges. The conditions of establishment and the nature of the evolution of the two main types of instability of these systems are analyzed. Particular attention is paid to cases of vortex particle motion. Dust systems having parameters similar to those in laboratory experiments are modeled numerically. Calculations were made for charged particles in an external electric field and in the Earth's gravitational field using a molecular dynamics method