ORDERED STRUCTURES IN A NONIDEAL DUSTY GLOW-DISCHARGE PLASMA

The formation of ordered structures of charged macroparticles in a con stant-current neon glow-discharge plasma is investigated. Experiments were performed with two types of particles: thin-walled glass spheres 50-63 mu m in diameter and particles of Al2O3, 3-5 mu m in diameter. F ormation of quasicrystalline structures is observed in the standing st rata and in an artificially created double electric layer. The formati on of extended filamentary structures of macroparticles in the absence of visible stratification of the positive column has been observed fo r the first time. The influence of the discharge parameters on the for mation of the ordered structures and their melting is examined. The fo rm of the interaction potential between the charged macroparticles is considered, as well as changes in the conditions for maintaining the d ischarge in the presence of high concentrations of dust particles. (C) 1997 American Institute of Physics. [S1063-7761(97)00912-8].