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arXiv · 2010.03770

Shock width measured under liquid and solid conditions in a 2D dusty plasma

Anton Kananovich·J. Goree
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Abstract

Widths of shocks are compared, under liquid and solid conditions, for a two-dimensional layer of charged microspheres levitated in a plasma. In this strongly coupled dusty plasma, a shock was launched as a blast wave by moving an exciter wire at a supersonic speed and then bringing it to a halt. Runs were repeated with the layer of microspheres prepared two ways: a crystalline-like solid, and a liquid. The liquid was sustained using laser heating, with conditions that were otherwise the same as in the solid. The shock width was found to be less in a liquid than in a solid, where it was 4 to 6 lattice constants. These measurements were based on the high-gradient region of density profiles. The profiles were obtained from particle coordinates, measured by high-speed video imaging. The spatial resolution was improved by combining particle coordinates, in the shock's frame of reference, from a sequence of images.

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Anton Kananovich, J. Goree. 2020-10-08. Shock width measured under liquid and solid conditions in a 2D dusty plasma. https://doi.org/10.1103/physreve.104.055201

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