托卡马克等离子体中存在C、N、O、Fe、Mo、Ni等杂质,这些杂质的存在对等离子体的特性有着重要的影响。在高温等离子体中,尤其是在中心区,杂质辐射主要在真空紫外光谱区。所以,对托卡马克等离子体的真空紫外光谱研究是十分重要的。它常用于测定杂质的种类、含量,也能测量等离子体参数如电子温度、离子温度等。这就需要对光谱强度进行定量的测量。为此必须对整个测量系统、包括谱仪及探测器等进行绝对标定。目前可见光区光谱的绝对校准已经解决,使用的黑体辐射源和次级标准源如钨带灯和碳弧等都是比较好的标准源。但是,在真空紫外光谱区尤其是在小于100nm的波段里,在国内还缺少比较好的方便的标准源。虽然迄今已建成电子同步辐射加速器,其高能电子发射从远红外线到X射线区的 The tokamak plasma contains C, N, O, Fe, Mo, Ni and other impurities, and the presence of these impurities has an important influence on the characteristics of the plasma. In high-temperature plasma, especially in the central region, the impurity radiation is mainly in the vacuum ultraviolet region. Therefore, it is very important to study the vacuum ultraviolet spectrum of tokamak plasma. It is often used to determine the type of impurity, content, but also to measure plasma parameters such as electron temperature, ion temperature. This requires a quantitative measurement of spectral intensity. For this purpose, the entire measuring system, including the spectrometer and detector, must be absolutely calibrated. At present, the absolute calibration of the spectrum of the visible light region has been solved. The blackbody radiation sources used and the secondary standard sources such as tungsten lamps and carbon arcs are all good standard sources. However, in the vacuum ultraviolet region, especially in the band of less than 100 nm, there is still a lack of a convenient standard source in China. Although the electron synchrotron has so far been built, its high-energy electron emission from the far infrared to the X-ray region