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arXiv · 1112.5316

Tracking shocked dust: state estimation for a complex plasma during a shock wave

Neil P. Oxtoby·Jason F. Ralph·Céline Durniak·Dmitry Samsonov
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Abstract

We consider a two-dimensional complex (dusty) plasma crystal excited by an electrostatically-induced shock wave. Dust particle kinematics in such a system are usually determined using particle tracking velocimetry. In this work we present a particle tracking algorithm which determines the dust particle kinematics with significantly higher accuracy than particle tracking velocimetry. The algorithm uses multiple extended Kalman filters to estimate the particle states and an interacting multiple model to assign probabilities to the different filters. This enables the determination of relevant physical properties of the dust, such as kinetic energy and kinetic temperature, with high precision. We use a Hugoniot shock-jump relation to calculate a pressure-volume diagram from the shocked dust kinematics. Calculation of the full pressure-volume diagram was possible with our tracking algorithm, but not with particle tracking velocimetry.

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Neil P. Oxtoby, Jason F. Ralph, Céline Durniak, Dmitry Samsonov. 2011-12-22. Tracking shocked dust: state estimation for a complex plasma during a shock wave. https://doi.org/10.1063/1.3678201

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