Experimental Investigations of Transport Properties of Partially Ionized Gases

Recent advances in electric are research and development allow stable high-temperature environments to be obtained over extended periods of time in the laboratory. By making use of the known relationships between temperature and conductivity in such are discharges and by experimentally measuring the current density, electron density, and temperature, the effective cross section of atoms which impede the electron flow can be determined. Thus, atom-electron collision cross sections can now be measured in the interesting energy range of 1 to 2 ev, lower than heretofore possible using conventional beam apparatus. Techniques involved in making the necessary spectroscopic and electrical measurements are given, and results obtained for three gases (argon, helium, and nitrogen) are presented. These results are then used to determine several of the transport properties for these partially ionized gases.