非軸対称トーラスプラズマにおける三次元MHD平衡・安定性と高エネルギー粒子

在托卡马克、仿星器等环形等离子体中，研究等离子体的磁流体动力学特性与α粒子等高能粒子之间的关系，对于实现热核聚变反应堆是必不可少的。本文对非轴对称环面等离子体中三维MHD平衡/稳定性与高能粒子之间的关系进行了以下理论和数值分析：1）利用基于仿星器近似的MHD稳定性程序研究了Alfvan连续谱带隙中的离散本征模。结果表明，由于等离子体β的有限性，转动变换轮廓的变化改变了TAE模式的模式结构和频率。高能粒子对TAE模的动力学效应目前正在微扰研究中。2）基于WKB近似的局部分析和三维理想MHD稳定性的整体分析都表明，TAE模的动力学效应是由高能粒子的运动学效应引起的。 关于我们 对螺旋系统特有的气胀模式进行了CAS 3D分析。通过对局部分析和整体分析的详细比较，验证了局部分析的有效性，并指出局部分析的近似有效性是值得怀疑的。为了估计动力学效应如何改变理想的气球模式，局部分析解决动力学气球模式方程。我们发现，有限Larmor半径（FLR）效应稳定了短波长模式，而压缩性对稳定长波长模式是有效的。3）已经开始开发蒙特-卡罗程序，从粒子的角度作为最终目标来估计动力学效应。第一步，研究螺旋系统中等离子体的新经典输运。Heliotron J.虽然很难定量地论证结果，但定性地验证了由于颠簸场分量和径向电场引起的新经典输运的抑制，这在以前的研究中得到了证实。4）在波纹托卡马克的分析中，考虑环形线圈的离散性，用Biot-Savart程序KMAG和三个非线性有限元程序KMAG得到自由边界MHD平衡。三维MHD平衡程序VMEC。阐明了环向场涟漪的有限β依赖性及其对高能粒子涟漪损耗的影响。少

In torus plasmas such as tokamaks and stellarators, investigation of the relation between MHD properties of the plasma and high energy particles like alpha particles is inevitable and important to realize a thermo-nuclear fusion reactor. In this study, following theoretical and numerical analyses are performed concerning the correlation between three-dimensional MHD equilibrium/stability and high energy particles in non-axisymmetric torus plasmas;1) Discrete eigenmodes existing in the spectral gap of Alfvan continuum are studied by using a global MHD stability code based on the stellarator approximation. It is found that the mode structure and frequency of the TAE modes are changed by the change of the rotational transform profile due to the finite plasma beta. The kinetic effect of high energy particles on the TAE mode is being studied perturbatively now.2) Both the local analysis based on the WKB approximation and the global analysis by using a three-dimensional ideal MHD stability c … More ode CAS3D are performed for the ballooning mode specific to the helical system. From the detailed comparison between the local and global analysis, the availability of the local analysis, in which the validity of the approximation is pointed out to be questionable, is verified. In order to estimate how the kinetic effect can change the ideal ballooning mode, local analyses solving the kinetic ballooning mode equations are done. We found that the finite Larmor radius (FLR) effect stabilizes short wave length modes and the compressibility is effective to stabilize long wave length modes.3) Development of a Monte-Carlo code has been started to estimate kinetic effects from the view point of particles as a final goal. At the first step, the neoclassical transport is being investigated for a plasma in a helical system. Heliotron J. Though it is difficult to argue the results quantitatively, suppression of the neoclassical transport due to the bumpy field component and the radial electric field, which is demonstrated in the previous studies, is verified qualitatively.4) In the analysis of a rippled tokamak, free-boundary MHD equilibria are obtained by considering discreteness of toroidal coils using a Biot-Savart code KMAG and a three-dimensional MHD equilibrium code VMEC. Finite beta dependence of the toroidal field ripple and its effect on the ripple loss of high energy particles are clarified. Less