Charge fluctuations for particles on a surface exposed to plasma

T. E. Sheridan; A. Hayes

doi:10.1063/1.3560302

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arXiv · 1102.1986

Charge fluctuations for particles on a surface exposed to plasma

T. E. Sheridan·A. Hayes

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Abstract

We develop a stochastic model for the charge fluctuations on a microscopic dust particle resting on a surface exposed to plasma. We find in steady state that the fluctuations are normally distributed with a standard deviation that is proportional to $CT_{e})^{1/2}$, where $C$ is the particle-surface capacitance and $T_{e}$ is the plasma electron temperature. The time for an initially uncharged ensemble of particles to reach the steady state distribution is directly proportional to $CT_{e}$.

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T. E. Sheridan, A. Hayes. 2011-02-09. Charge fluctuations for particles on a surface exposed to plasma. https://doi.org/10.1063/1.3560302

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