The detection of microparticles prior to vacuum breakdown using a laser scattering technique

Abstract
Reports on the preliminary results obtained with a new method of microparticle detection using forward scattering from a focused 4 W argon ion laser beam. For the first time microparticles are shown to be present in the interelectrode gap in the few microseconds prior to vacuum breakdown. The frequency of occurrence is high and it is shown that many of the observations cannot simply be explained as being due to microparticles leaving the anode under uniform acceleration as is usually assumed for conventional microparticle breakdown theories.