Instability of dust-acoustic waves in partially ionized collisional dusty gases

A linear dispersion relation for an electrostatic dust-acoustic wave (DAW) has been derived, taking into account dust charging collisions and dust charge fluctuations in partially ionized dusty plasmas. It is found that there exist a departure from the Boltzmann ion response when the variation of charging collisions owing to dust charge perturbations is self-consistent incorporated in the ion continuity equation. Consideration of variable charging collisions leads to an instability of the dust-acoustic waves. The present investigation thus offers a novel mechanism for the excitation of DAW in low-temperature, partially ionized laboratory dusty gas discharges.