DOI: 10.1063/5.0337888 ISSN: 1070-664X
Charging of dust in plasma
L. S. MatthewsObjects immersed in a plasma become charged as the plasma particles (electrons and ions) collide with the surface. The problem of determining the electric potential on an object ranges from the charge on spacecraft to the potential of probes inserted into a plasma as a diagnostic device. Here, we derive the expressions used to calculate the charge on a spherical dust grain in a homogeneous, isotropic plasma, commonly referred to as the Orbital Motion Limited (OML) theory. The basic assumptions underlying the OML theory are discussed as well as its limitations. The physics underlying the OML model for charging is relevant to any plasma-facing surface and is applicable to a broad range of plasma environments.