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Experiments with extended three-dimensional dusty plasmas under microgravity conditions were performed to study the complex wave pattern of self-excited dust-density waves and its interaction with the plasma. The simultaneous observation of the dust-density fluctuations and the plasma glow revealed that the observed wave phenomenon affects the plasma in the complete discharge. In particular, our investigations suggest, that self-excited dust-density waves are the product of a self-organized system consisting of the dust cloud, the plasma, and the external circuit. The complex wave pattern is a consequence of partial synchronization of neighboring regions inside the dust cloud and can be modeled by a system of coupled nonlinear oscillators. [ABSTRACT FROM AUTHOR]

A chain of mutually coupled nonlinear and self-sustained oscillators is studied numerically. The simple model allows to explain the topological structure of self-excited dust-density waves under microgravity conditions. The basic properties of the model are presented and compared with experimental studies. [ABSTRACT FROM AUTHOR]

The dynamical properties of individual particles in a dusty plasma under microgravity conditions are investigated by means of a stereoscopic camera setup. This camera system allows the three-dimensional reconstruction of particle trajectories in a volume of approximately (15×15×15) mm3 in three dimensions. We present measurements in two different regions of a dust cloud on parabolic flights. First, the force field in the void is reconstructed from probe particles in three dimensions. Second, the oscillation of particles at the outer dust cloud surface is evaluated, and the relation to dust-density waves in the dust cloud is investigated. [ABSTRACT FROM AUTHOR]