Measurement of the ion drag force on falling dust particles and its relation to the void formation in complex (dusty) plasmas
Measurement of the ion drag force on falling dust particles and its relation to the void formation in complex (dusty) plasmas
复制标题
测量落下尘埃颗粒上的离子曳力及其与复杂（尘埃）等离子体中空隙形成的关系
DOI：
10.1063/1.1569486
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发表时间：
2003
影响因子：
2.2
通讯作者：
A. Piel
中科院分区：
文献类型：
--
作者：
C. Zafiu;A. Melzer;A. Piel
本文介绍了在射频放电管中对自由下落的尘埃粒子施加的较弱力（离子拖曳力、热泳力和电场力）的定量测定实验。最强的力，重力，是平衡的气体摩擦和较弱的力量，在径向（水平）平面。在大多数放电条件下，粒子被发现从中央等离子体区域排出。在低气压下使用小颗粒观察到向下落的颗粒被聚焦到等离子体中心的情况的过渡。这些调查可以定量了解微重力下尘埃等离子体中不必要的无尘区域（所谓的空隙）的机制。良好的定量协议与标准模型的离子阻力。
Experiments on the quantitative determination of the weaker forces (ion drag, thermophoresis, and electric field force) on free-falling dust particles in a rf discharge tube are presented. The strongest force, gravity, is balanced by gas friction and the weaker forces are investigated in the radial (horizontal) plane. Under most discharge conditions, the particles are found to be expelled from the central plasma region. A transition to a situation where the falling particles are focused into the plasma center is observed at low gas pressures using small particles. These investigations allow a quantitative understanding of the mechanism of unwanted dust-free areas (so-called voids) in dusty plasmas under microgravity. Good quantitative agreement with standard models of the ion drag is found.