Coulomb Cluster in a Plasma under Cryogenic Environment
نویسندگان
چکیده
Coulomb cluster of dust particles in an RF helium plasma under cryogenic environment is observed experimentally. Background neutral temperature is controlled by cryogenic liquid such as liquid helium or liquid nitrogen. Dust dynamics in a sheath is studied. A dust injected into a sheath moves toward an equilibrium position where the sheath electric force balances with the gravitational force. Dust charge determined by oscillatory motion around the equilibrium position is found to decrease with decreasing ion temperature. A Coulomb cluster is formed in a horizontal plane and the temperature dependence of the interparticle distance in the cluster is studied.
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