Dust grain charging and levitation in a weakly collisional sheath
نویسندگان
چکیده
An experiment is described in which monodisperse dust grains are levitated within a dc sheath above a conducting plate in argon plasma. For plate bias voltages that are not too negative ~>210 electron temperatures!, the observed dust levitation heights are near to values calculated from a model combining equations for the sheath with those for grain charging. When the plate is more negatively biased, the theoretical levitation heights are higher than the observed heights as a consequence of the measured sheath thickness being smaller than values obtained from the models. © 2003 American Institute of Physics. @DOI: 10.1063/1.1612941#
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