等离子体离子源发射面的理论计算与数值模拟

 等离子体离子源发射面的位置和形状决定了离子束的传输特性，而发射面的位置与形状又取决于等离子体参数、引出电压、电极结构等，并自动地调节到某个平衡状态。介绍了一种2维情况下等离子体离子源发射面的位置与形状的理论计算方法，即非磁化等离子体不能扩散进入外加电场中大于一定临界值的区域，等离子体离子源发射面的位置及形状可以通过直接求解引出系统的Laplace方程而得到。利用基于PIC的OOPIC程序对不同引出结构的发射面位置及形状和引出束流进行了数值模拟，结果与理论计算的结果十分接近。

Estimation and simulation of emitting surface in plasma ion source

The location and the shape of emitting surface in plasma ion source determine the extraction character of ion beam, and they always depend on the parameters of plasma, the configuration of electrodes and the extraction voltage, etc. They always automatically adjust to a certain state. In this paper, a 2D theoretical method to estimate these two factors, namely, an unmagnetized plasma can not penetrate a region with an applied vacuum dc electric field magnitude above a critical value. Thus the location and the shape of ion emitting surface can be found by solving the equation of Laplace of extraction system directly. Simultaneously, numerical simulation experiments of the location and the shape of ion emitting surface and the extraction beam current in different extraction systems based on