INTERACTION OF GRAINS IN DUSTY PLASMAS

Plasma absorption by dust grains results in anisotropy of plasma distr ibution function. This yields the effective attractive interaction bet ween grains. Here a brief review of physical properties of this intera ction is given. First we demonstrate that there is the attracting forc e between two grains obeying the inverse square low. Then a set of kin etic equations taking into account both attracting and repulsing force s is proposed. We study a simple model of a dust cloud consisting of f inite number of grains. It is shown that even within gaseous approxima tion a dust cloud is a compact object with a sharp boundary. Finally, we discuss recent experiments aimed to detecting the attractive force between massive bodies.