发表机构
The University of Texas at Austin; University of Sydney; University of Colorado, Boulder（德克萨斯大学奥斯汀分校; 悉尼大学; 科罗拉多大学博尔德分校）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本文利用外微分系统和Cartan-Kähler定理证明，在Boozer坐标中任意正解析函数均可局部实现为磁场强度，故无局部解析障碍。
AI 中文摘要
磁场强度是等离子体磁约束理论中的核心设计对象。理想的约束性质，如准对称性和全对称性，当磁场强度在称为“Boozer坐标”的特殊坐标系中给出时，由场强的特殊形式表征。我们提出一个基本的可实现性问题：哪些Boozer坐标的函数可以作为以Boozer坐标书写的磁场的大小出现？利用外微分系统和Cartan-Kähler定理，我们证明每个正解析函数都是局部可实现的。因此，在Boozer坐标中规定场强不存在局部解析障碍；尽管进一步的限制可能来自全局几何或额外的物理约束。
英文摘要
The magnetic field strength is a central design object in the theory of magnetic confinement of plasma. Desirable confinement properties such as quasi-symmetry and omnigenity are characterized by special forms of the field strength when it is given in the particular coordinate system called ``Boozer coordinates." We ask a basic realizability question: which functions of Boozer coordinates can arise as the magnitude of a magnetic field that is written in Boozer coordinates? Using exterior differential systems and the Cartan-Kähler theorem, we show that every positive analytic function is locally realizable. Thus there is no local analytic obstruction to prescribing the field strength in Boozer coordinates; though further restrictions might arise from global geometric or additional physical constraints.
