利用低能EBIT 模拟麦克斯韦能量分布的等离子体研究

托卡马克等离子的光谱十分复杂,通常电子束离子阱（EBIT）装置能为分解研究托卡马克等离子体提供基本的原子参数，如能级结构，各个原子过程的反应截面等。通过EBIT 产生麦克斯韦-波尔兹曼能量分布的单一元素特定温度下的等离子体并得到其光谱，属于具有 EBIT 特色的研究手段。该方法的可行性已经由美国的利弗莫尔实验室利用EBIT 论证过，但其在等离子体诊断应用方面的研究尚未有报道。本项目利用实验室自主开发的超低能EBIT（其电子束能量下限已经达到30电子伏特，在国际上排名第一），再运用扫描EBIT 电子束能量的方法，将首次在EBIT 上模拟出温度只有数百电子伏特的托卡马克边界等离子体（主要是碳和钨两种元素），同时得到的高精度光谱可作为一种标准谱为托卡马克边界等离子体的光谱诊断提供对比参考。

The spectrum of Tokamak plasma are very complicated, usually an Electron Beam Ion Trap (EBIT) can provide some basic atomic parameters such as level structure and cross sections for studying Tokamak plasmas. The spectrum of the plasma from single element under the specific temperature can be directly obtained from an EBIT, it can provide more direct basis for plasma diagnostics. This technique has been proved by Lawrence Livermore National Lab using its own EBIT, but there is no report about its application on plasma diagnostics. In this project, our low-energy EBIT's lower energy limit is 30 electron volts , which sets the record among the reported works so far. We will scan the electron beam energy to simulate the Tokamak boundary plasma （tungsten and carborn） whose temperature is only around several hundred electron volts. Furthermore, high-precision measurements of these spectrum can be used as a reference in the Tokamak boundary plasma diagnostics.