The effect of the type of ion–neutral collisions on ion cloud formation

Abstract

In this paper, the effect of ion–neutral collision type on the ion cloud formation around a dust particle immersed in plasma in the presence of an external electric field is considered. It is shown that elastic ion–neutral collisions in low-temperature low-density plasma lead to the persistence of directed velocity compared to the resonant charge exchange collisions, where ions lose almost their energy. Thus the ion drift velocity is larger for the case of elastic collisions than for resonant charge exchange collisions. With the increase of an external electric field strength, the charge of dust particle increases faster for the elastic case than for resonant case. The dipole moment of the ion cloud–dust particle system is also appeared to have higher values for the case of elastic collisions.