  Motivated by experiments on the generation of streaming plasmas in high
energy density facilities, industrial setups, and fundamental dusty plasma
research the plasma polarization around a test charge in streaming plasmas is
considered. The induced charge density distribution of plasma constituents is
discussed for the subsonic, sonic, and supersonic regime. Also, it is shown
that the plasma polarization in the vicinity of the test charge shows different
scaling in subsonic and supersonic regimes.
