Dust flows in nonlinear dust-acoustic waves in plasma

A linear theory of harmonic dust-acoustic waves in dusty plasma has been constructed. Within its framework, the law of dispersion of such waves was established and a formula for the dust sound speed was derived. A nonlinear theory of dust-acoustic waves was also developed, within the framework of which a formula for the Sagdeev pseudopotential was obtained. Analysis showed the existence of subsonic periodic dust-acoustic waves and supersonic dust-acoustic solitons. The average flowes of dust grains in a periodic dust-acoustic wave and in a sequence of dust-acoustic solitons are calculated. It is shown that the flow of dust grains in a periodic dust-acoustic wave is directed against the wave phase velocity and, conversely, the flow of dust grains is transported by solitons in the direction of their movement.