Dust-Plasma Sheath: the Sheath Thickness and the Energy of the Grain

A dust grain in plasma acquires an electric charge by collecting ions and electrons from the plasma. The presence of charged dust grains can significantly affect the behavior of plasma in which they are immersed because of their unusual value of charge-to-mass ratio. Both electrons and ions will be collected by the dust grains, but since the electrons move about more swiftly than the ions; the grains tend to acquire a negative charge. Under the simplest approximation, all the dust grains may be considered to have the same mass and equilibrium charge, and so they are equivalent to a second ion species. In this work an attempt is made to give the impact energy of dust particle at the wall (electrode) and the sheath thickness. The theory and numerical results are presented for collisional dusty plasma.