Plasma Polarization Spectroscopy (PPS) : Its Development and Diagnostics Application

在Kato(大阪)和Fujimoto(京都)的联合实验中，我们发现类新生锗的x射线激光辐射偏振20-50%。从激光跃迁较低能级的共振线的各向异性辐射陷阱被确定为偏振的原因。WT-3装置(京都)的杂质离子(类硼、类铍氧和类氦碳)谱线在低杂波电流驱动和电子回旋加热两个阶段被极化。对激光产生的氟等离子体在复合等离子体模式下的光谱进行了偏振分析，发现类氦共振线和复合连续谱是偏振的。这些事实表明，偏振并不是一种特殊的现象，但在许多情况下，等离子体发射往往是偏振的。为了将观测到的偏振与等离子体的空间各向异性或非热性质相结合，建立了对准碰撞-辐射模型。这是通常用来分析等离子体中布居动力学的布居碰撞扩散模型的推广。这种新模型所需要的截面正在计算中，例如电子碰撞产生的取向截面。PPS的仪器已经开发出来：在分光计中引入方解石板，两个极化分量被分离并同时测量；液晶被用来观测日冕；CCD探测器被用作偏振敏感设备。

In the joint experiment by Kato (Osaka) and Fujimoto (Kyoto) , we have found that the neonlike germanium x-ray laser radiation is polarized by 20-50%. The anisotropic radiation trapping of the resonance line from the lower level of the laser transition is identified as the cause of the polarization. Impurity ion (boronlike-and berylliumlike oxygen and heliumlike carbon) lines from the WT-3 tokamak (Kyoto) is found polarized at the biginning of the lower-hybrid current drive and the electron-cyclotron heating. Polarization was examined of the spectrum of the laser-produced fluorine plasma in the recombining plasma mode, and the heliumlike resonance line and the recombination continuum were found polarized. These facts suggests that polarization is not a special phenomenon but plasma emissions tend to be polarized in many cases.For the purpose of combining the observed polarization to the spatial anisotropy, or non-thermal properties, of the plasma the alignment collisional-radiative model has been developed. This is an extension of the population collisionalraidative model that is commonly employed to analyze the population kinetics in plasma. The cross section necessary in this new model, e.g., the alignment creation cross section by electron impacts, is being calculated.Instrumentation for PPS has been developed : A calcite plate is introduced in a spectrometer and the two polarized components are separated and measured simultaneously ; Liquid crystals are used for observation of the solar corona ; The CCD detector is used as a polarization sensitive equipment.