Thermally and electrically induced bubbles in liquid argon and nitrogen

An experimental study of high field conduction phenomena in liquid argon and liquid nitrogen in a point-plane electrode geometry is reported. These liquids behave qualitatively like saturated hydrocarbons except when they are studied close to their normal boiling point. The generation and dynamics of microscopic bubbles (thermally and electrically induced) as a function of various parameters (nature of the liquid, injected energy, hydrostatic pressure) are presented and discussed. Possible influences of these phenomena on the electrical insulation at cryogenic temperatures is also discussed.