Precise Measurement of Refractive Index of Liquid Xenon Scintillator

用自行研制的仪器测量了液体氙闪烁体在闪烁光下的折射率，测量精度优于0.01。主要结果如下：--我们成功地获得了气相与液体氙气相平衡时的折射率，最小误差为0.007。从可见光到真空-紫外区，折射率的值随波长变化在1.38到1.71之间。在可见光区，测量结果与以往的高精度实验结果基本一致。折射率的波长依赖关系遵循著名的Sellmeier色散方程。-在真空-紫外区，我们也测量了与其气体平衡的0.9×10~(-5)和1.2×10~(-5)帕的折射率，观察到折射率的微小变化。我们发现，密度依赖关系可以用洛伦兹-洛伦兹关系很好地解释。得到的指数值与以前…的任何值都有显著差异更巧妙地研究了真空紫外区。我们讨论了产生差异的原因，并指出了以前实验中可能产生误差的原因。根据额外的校准工作，我们已经证实了我们的实验所声称的高精度。-研究的进展和结果已在各种学术会议和硕士论文中报告。国际上一本关于惰性气体探测器的书中引用了部分结果。我们指出，折射率是计算氙液中瑞利散射长度的重要参数，而闪烁光谱目前还不是很清楚。此外，我们还揭示了作为副产物的氙气的相变所涉及的一个新问题。此外，我们还揭示了作为副产物的氙气的相变所涉及的一个新问题。研究结果表明，在一个压力下，氙气的沸点可能比已知值高出约1K。对于折射率的研究来说，这种差异是可以忽略不计的，但它很重要，应该通过未来液体氙气的各种应用研究来解决。较少

We have measured refractive index of liquid xenon scintillator for scintillation light with good precision of less than 0.01 by using originally developed apparatus. The main results are the following :- We have successfully obtained the refractive index of liquid xenon in equilibrium with its gas phase at 10^5 Pa with a least error of 0.007. The value of the index varies from 1.38 to 1.71 as a function of wavelength from visible to vacuum-ultraviolet region. At visible region, the measured values are consistent with those by previous high-precision experiment. The wavelength dependence of the index is followed by well-known Sellmeier dispersion equation.- At vacuum-ultraviolet region, we measured the index also at 0.9x10^5 and 1.2x10^5 Pa similarly in equilibrium with its gas to observe slight change of the index. We found out that the density dependence is well explained by Lorentz-Lorenz relation.- The obtained value of the index is significantly different with any values of previou … More sly studies at vacuum ultraviolet region. We discuss the reasons of the difference and pointed out that the possible cause of errors in the previous experiments. We have confirmed the claimed high precision of our experiment based on additional calibration works.- The progress and the results of the study have been reported at various academic meetings as well as in master's theses. A part of the results has been referred in an international book on noble gas detectors.We have pointed out that the refractive index is important quantity to calculate Rayleigh scattering length in xenon liquid, together with scintillation spectrum which is still not well known yet. In addition, we have revealed a new problem involved in phase transition of xenon as a by-product. In addition, we have revealed a new problem involved in phase transition of xenon as a by-product. The results of the study indicate that the boiling point of xenon might be about 1 K higher than known value at a pressure. This discrepancy is negligibly small enough for the study of the refractive index, but it is important and should be resolved by future studies for various applications of liquid xenon. Less