Influence of a charge-gradient force on dust acoustic waves

The influence of a charge-gradient force, associated with variations of the particle charge in response to external perturbations, on the propagation of low-frequency waves in weakly coupled complex (dusty) plasmas is investigated. The magnitude of the effect is compared with that due to polarization force, studied previously in the literature. Numerical estimates are presented for the regime, where the orbital motion limited approach to particle charging is relevant.