Langmuir probe and ion acoustic velocity measurement of the concentration of two species in a multi-dipole plasma

Summary form only given, as follows. The concentration of two species in a multi-dipole plasma was determined by measuring the ion acoustic wave group velocity and the electron temperature in a multi-dipole plasma device. The wave was launched from a grid immersed in the plasma and was detected by a probe. Electron temperature was found separately from a Langmuir probe trace. The technique was performed in helium/xenon and argon/xenon plasmas. Typical parameters of the plasma were T/sub e//spl sim/0.5 to 3 eV, density 10/sup 10/ cm/sup -3/, plasma potential of 3 to 5 V and pressure range from 1 to 20 mTorr.