Applications of electron beams for precise switching of high voltages

An advanced, externally triggered, spark gap switch, capable of closing in a few nanoseconds, with subnanosecond statistics, is being developed. One of the principal parameters that determines the characteristics of a spark gap switch is the nature of the space charge produced in the gap by the triggering mechanism. In this paper, we describe the application of a 200 keV, .5 kA, pulsed electron beam for precise switching of high voltages. Using this beam as the source of space charge, we have been able to switch voltages up to 500 kV with nanosecond statistics. The characteristic of the electron gun, the experimental switching arrangement, the results obtained with this arrangement, and the desirable characteristics of this switching technique are discussed.