Ion–acoustic waves in dusty plasma with charge fluctuations

In the present investigation it is emphasized that dust particles in a plasma introduce two widely separated, slow and fast, temporal scales, namely dust acoustic and charge fluctuation time scales, which emanates from the large inertia of the dust, and from its collision with plasma particles, respectively. It is demonstrated that, at fast time scales, it is the collective behavior of plasma particles (electrons and ions) which is affected by dust charge fluctuation. The existence of an ion temperature threshold above which the ion–acoustic mode can become unstable due to the fluctuation of the dust charge is shown.