SHIELDING OF A SLOWLY MOVING TEST CHARGE IN DUSTY PLASMAS

The far-field potential of a slowly moving test charge in dusty plasma s is calculated accounting for the dust grain charge fluctuations. It is found that the latter cause a damping, which in turn gives rise to a dipole-like far-field potential. The presence of the dipole-like pot ential is attributed to the dust grain charge perturbations caused by the oscillating electron and ion currents induced by the motion of a t est charge.