论文标题
在没有闭合场的非对称磁场的X点附近带电的粒子动力学
Charged particle dynamics near an X-point of a non-symmetric magnetic field with closed field lines
论文作者
论文摘要
了解粒子在非对称磁场中的漂移是设计优化的恒星剂以最大程度地减少颗粒的新古典径向损失的主要兴趣。准对称和异性，这是提出的两种不同的特性，以确保恒星中无碰撞的无缠绕颗粒的径向定位，几乎仅针对产生嵌套通量表面的磁场进行了探索。在这项工作中，我们将这些概念扩展到关闭所有场线的情况。然后，我们研究了具有X点的确切非对称真空磁场中带有封闭场的带电颗粒动力学，该磁场是Weitzner和Sengupta（Arxiv：1909.01890）最近获得的，该磁场具有X点。磁场可用于在消失的血浆压力的极限下构建磁流失动力平衡。在非对称场的幅度扩大，我们明确评估了异性性和准对称约束。我们表明，从漂移表面与压力表面一致的意义上，磁场是不合格的。但是，根据标准定义不是准对称的。
Understanding particle drifts in a non-symmetric magnetic field is of primary interest in designing optimized stellarators to minimize the neoclassical radial loss of particles. Quasisymmetry and omnigeneity, two distinct properties proposed to ensure radial localization of collisionless trapped particles in stellarators, have been explored almost exclusively for magnetic fields that generate nested flux surfaces. In this work, we extend these concepts to the case where all the field lines are closed. We then study charged particle dynamics in the exact non-symmetric vacuum magnetic field with closed field lines, obtained recently by Weitzner and Sengupta (arXiv:1909.01890), which possesses X-points. The magnetic field can be used to construct magnetohydrodynamic equilibrium in the limit of vanishing plasma pressure. Expanding in the amplitude of the non-symmetric fields, we explicitly evaluate the omnigeneity and quasisymmetry constraints. We show that the magnetic field is omnigeneous in the sense that the drift surfaces coincide with the pressure surfaces. However, it is not quasisymmetric according to the standard definitions.
