A model of coagulation in dust clouds during grain charging Original Research Article

Initially uncharged grains in space and laboratory plasma environments become charged due to currents driven by potential differences in the dusty plasma. Certain macroscopic effects such as coagulation of smaller grains into larger ones or fluffy aggregates can be affected during this initial grain charging phase. The charging profiles of micron- and submicron-sized dust grains immersed in such plasma environments are strongly size- and temperature-dependent, and under certain conditions, the dust cloud can have various configurations of charged grains. Using a standard grain charging model along with a modified Barnes–Hut tree code for calculating grain dynamics, this paper examines the effect of including initial grain charging in coagulation of clouds of negative grains, positive grains, and a mixture of oppositely charged grains. The immediate application to coagulation during transient dusty plasma conditions is discussed.