Dynamics of dust particles coming off a wall in sheath and presheath

Smirnov, R.*; Tomita, Yukihiro*; Takizuka, Tomonori; Takayama, Arimichi*; Chutov, Y.*

Dynamics of a single dust particle in near-wall plasma is studied in wide range of dust radii and masses. Dust motion and charging equations are solved in the plasma simulated for sheath and ionizing presheath using one-dimensional particle model. It was found that balance of electric and ion drag forces acting on the dust particle provides two critical dust radii differentiating motion of dust started at the wall between pinned against the wall, short and long-range oscillating. Delayed charging causes the mass dependence of the second critical radius until transition from short to long-range oscillations becomes undistinguishable.