Studies of electrical breakdown processes across vacuum gaps between metallic electrodes

An experimental program to elucidate the physical causes of electrical breakdown across vacuum gaps, such as those that occur in charged particle accelerators, is discussed. Magnetic insulation is explored as a technique to differentiate between field emission of electrons and clump acceleration as possible causative mechanisms for the onset of breakdown. The results and limitations of an exploratory experiment are described, along with plans for a more comprehensive experimental and theoretical campaign.