高压氘氚靶球的制备与拉曼光谱研究

氢同位素的定量分析与监测在能源与环境领域都有着重要的意义。激光拉曼光谱由于其可以无损分析氢同位素分子，已经成为一种重要的方法，在国际热核聚变实验反应堆(ITER)和美国萨凡纳河工厂得到了广泛应用。利用高压充气装置得到了惯性约束聚变(ICF)高压靶丸，并对靶丸内气体进行原位拉曼光谱测量，通过对高压下氘氚混合气体的拉曼光谱进行分析得到了靶丸内气体的成分比例，验证了靶丸充气工艺参数。实验表明，在CCD的积分时间延长到1 min时，氘(DD)，氘氚(DT)和氚(TT)的测量精度可以达到1%，同时对不同时刻靶丸内气体组分的拉曼光谱进行测量，实验结果表明在氘氚渗透和氚衰变两者共同作用下，靶丸内总气体压力随时间不断下降，但是气体组成基本不发生变化。

Preparation and Raman Investigation of High Pressure ICF Targets

The quantitative analysis and monitoring of hydrogen isotopes, including hydrogen (H₂), hydrogen deuterium (HD), hydrogen tritium (HT), deuterium (D₂), deuterium tritium (DT) and tritium (T₂), are of great significance in the field of energy and environment. Due to its non-destructive and non-contact analytical characteristics, laser raman spectroscopy (LRS) has become an important analyzing method for hydrogen isotopes quantification and in-line monitering. In the international thermonuclear experimental reactor (ITER) and savannah river factory (SRF) laser raman spectroscopy has been extensively used for qualitative and quantitative analytical purposes. Promising results are also obtained in raman system at the Karlsruhe Tritium Neutrino Experiment (KATRIN), which is targeted to measure the neutrino mass by means of high precision electron spectroscopy of the β-decay of tritium. In this paper, high pressure gas targets for inertial confinement fusion (ICF) experiments were prepared and studied by Raman spectroscopy. The composition of high pressure deutrium-tritium mixtrures were obtained by analyzing the rota-vibrational spectra of above molecules as a first approximation. The obtaining results were compared with mass spectroscpy measurements and the technological parameters for target fabrication were verified. The experiments showed that a precision of 1% can be obtained for deuterium (D₂), deuterium tritium (DT) and tritium (T₂) when integration time increased to 1 minute using a commercial instrument (LabRAM HR800,Jobin Yvon), though modification was still needed to achieve a even higher precesion. The pressure shifts for deuterium (D₂), deuterium tritium (DT) and tritium (T₂) were tentatively investigated and compared with previous studies. At the same time, the composition evolution of high pressure deuterium tritium gas mixture was also monitored during 6 months’ storage time. The experimental results show ed that due to the interplay of gas permeation and tritium decay effects, the gas composition did not change though the total gas pressure within the target decreased continuously with time.