The Dectection of Microparticle-Induced Breakdowns Using a Twin-Beam Laser Scattering System

Microparticles with radii less than 0.5 μm have been observed in a HV vacuum gap using a twin beam laser light scattering technique. For the geometry and electrode material used it has been shown that 97% of the particles travel from anode to cathode. Investigation of the correlation between the time of cathode impact and the time of breakdown indicates that most of the breakdowns are induced by microparicles.