Measurements of Ambipolar Diffusion in Helium

摘要: Microwave techniques are applied to the study of diffusion electrons and positive ions in helium. For electron ion densities realized experimentally, takes place ambipolarly; that is, flow charged particles both signs is equalized by space charge field which they set up. At 1 mm Hg pressure 0.039-ev average energy, measured value ambipolar coefficient, ${D}_{a}$, 540 ${\mathrm{cm}}^{2}$/sec. The variation ${D}_{a}$ with gas density, energy particles, container size shape agrees closely theory.