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Charge fluctuations for particles on a surface exposed to plasma

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 نشر من قبل Terrence Sheridan
 تاريخ النشر 2011
  مجال البحث فيزياء
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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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