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arXiv · 1307.2766

Autowaves in a dc complex plasma confined behind a de Laval nozzle

M. A. Fink·S. K. Zhdanov·M. Schwabe·M. H. Thoma·H. Höfner·H. M. Thomas·G. E. Morfill
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Abstract

Experiments to explore stability conditions and topology of a dense microparticle cloud supported against gravity by a gas flow were carried out. By using a nozzle shaped glass insert within the glass tube of a dc discharge plasma chamber a weakly ionized gas flow through a de Laval nozzle was produced. The experiments were performed using neon gas at a pressure of 100 Pa and melamine-formaldehyde particles with a diameter of 3.43 μm. The capturing and stable global confining of the particles behind the nozzle in the plasma were demonstrated. The particles inside the cloud behaved as a single convection cell inhomogeneously structured along the nozzle axis in a tube-like manner. The pulsed acceleration localized in the very head of the cloud mediated by collective plasma-particle interactions and the resulting wave pattern were studied in detail.

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M. A. Fink, S. K. Zhdanov, M. Schwabe, M. H. Thoma, H. Höfner, H. M. Thomas, G. E. Morfill. 2013-07-10. Autowaves in a dc complex plasma confined behind a de Laval nozzle. https://doi.org/10.1209/0295-5075%2F102%2F45001

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