Scattering of dust microparticles by collective oscillations of a plasma

A special gas-discharge chamber was designed, manufactured, and tested for investigating the regularities of Brownian scattering of dust grains in plasmas produced by a stationary dc glow discharge and a stationary high-frequency electric (HFE) discharge. An experimental procedure for studying Brownian scattering was developed. Records of dust grain scattering in the plasma are given. Mathematical processing of a large number of images of dust grains showed that the dependence of the dust grain distribution width in the images at half distance from the discharge to the sample stage on the discharge current strength is well approximated by a linear relation with a proportionality constant equal to approximately 16 mm/A. It is shown that the scattering is caused by collective oscillations of the plasma – pulsations of ionization type.