Gas rotation in discharges in a longitudinal magnetic field

This paper reviews theoretical and experimental work on gas rotation in discharges ignited in a longitudinal magnetic field. There is abundant evidence that such a field causes plasma-dust structures to rotate in the plane perpendicular to itself. This rotation cannot be explained solely by the dragging action of azimuthally moving ions. Drag is also exerted by the gas rotating under the moment produced by the Ampere force that arises in discharge regions with a nonuniform magnetic field near solenoid end faces and due to the narrowing of the discharge channel cross section. In a stratified discharge in a uniform magnetic field, an eddy electric current due to the noncollinearity of the plasma-density and temperature gradients brings the gas to rotation.