Measurements of the structure of the convection sustained ion sheath

Abstract

Probe measurements throughout a planar convection-sustained ion sheath reveal that upstream of the sheath: (a) no appreciable diminution of ionization density occurs, unlike the stationary continuum situation, and (b), there exists an electric field which is approximately equal to the ratio of the flow velocity to the electron mobility. Downstream of the sheath edge, measurements of the fall off of the ion and electron densities are reported. The above measurements are found to be in satisfactory agreement with the sheath convection theory of Smy.