Lieberman M A, Charles C
Space Plasma, Power and Propulsion, Research School of Physical Sciences and Engineering, Australian National University, ACT 0200, Australia.
Phys Rev Lett. 2006 Jul 28;97(4):045003. doi: 10.1103/PhysRevLett.97.045003. Epub 2006 Jul 26.
A diffusion-controlled theory is developed for the formation of a low-pressure, current-free double layer just inside an upstream insulating source chamber connected to a larger diameter, downstream chamber. The double layer is described using four groups of charged particles: thermal ions, monoenergetic accelerated ions flowing downstream, accelerated electrons flowing upstream, and thermal electrons. The condition of particle balance upstream is found to determine the double layer potential. The double layer disappears at very low pressures due to loss of ionization balance upstream and due to energy relaxation processes for ionizing electrons at higher pressures, in good agreement with experiments.
针对在连接到较大直径下游腔室的上游绝缘源腔内形成的低压、无电流双层，提出了一种扩散控制理论。使用四组带电粒子来描述双层：热离子、向下游流动的单能加速离子、向上游流动的加速电子和热电子。发现上游粒子平衡条件决定了双层电势。由于上游电离平衡的丧失以及在较高压力下电离电子的能量弛豫过程，双层在非常低的压力下消失，这与实验结果非常吻合。
