Investigation of carbon impurity transport in plasmas by using 13CH4

为了了解碳从侵蚀到沉积的输运过程，注入了^<13> CH_4，并对沉积^<13> C的分布进行了研究。结果表明，^<13> CH_4注入口前的碳瓦与H原子接触。因此^<13> C的可能输运过程如下：CH_4既没有解离成C和H，也没有电离，也没有沿着磁力线移动。但^<13> CH_4与碳瓦反复黏附再发射，以^<13> CH_x（x=1-4）的形式到达注入口前的碳瓦。

In order to understand the transport of carbon, from erosion to deposition,^<13> CH_4 was injected, and the distribution of the deposited^<13> C was investigated. It was found that^<13> C reached, with H atoms, the carbon tiles in front of the^<13> CH_4 injection port. Hence possible transport process of^<13> C is as follows ;^<13> CH_4 neither dissociated into^<13> C and H, nor ionized, nor traveled along the magnetic field lines. But^<13> CH_4 repeated sticking and reemission with carbon tiles and reached the carbon tile in front of the injection port in the form of^<13> CH_x(x=1-4).