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arXiv · 1401.7974

Mobility in a strongly coupled dusty plasma with gas

Bin Liu·J. Goree
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Abstract

The mobility of a charged projectile in a strongly coupled dusty plasma is simulated. A net force $F$, opposed by a combination of collisional scattering and gas friction, causes projectiles to drift at a mobility-limited velocity $u_p$. The mobility $μ_p=u_p/F$ of the projectile's motion is obtained. Two regimes depending on $F$ are identified. In the high force regime, $μ_p \propto F^{0.23}$, and the scattering cross section $σ_s$ diminishes as $u_p^{-6/5}$. Results for $σ_s$ are compared with those for a weakly coupled plasma and for two-body collisions in a Yukawa potential. The simulation parameters are based on microgravity plasma experiments.

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Bin Liu, J. Goree. 2014-01-30. Mobility in a strongly coupled dusty plasma with gas. https://doi.org/10.1103/physreve.89.043107

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