Charge injection into a liquid dielectric by means of x rays

Owing to the very small magnitude and erratic nature of the natural currents which flow in fluid dielectrics subjected to electrical stress, it is convenient to enhance the charge flow artificially when studying pre-breakdown phenomena. A new test cell designed for use with liquid dielectrics enables an ionized plasma to be established very close to one electrode. This mode of charge generation by x rays is not subject to the limitations imposed in more conventional injection techniques and results in a high conduction current. A theoretical analysis of the cell behaviour yields results which are in good agreement with experimental data, and shows that the arrangement is very suitable for the measurement of carrier mobilities in liquid dielectrics.