Relativistic guiding-center equations including slow equilibrium changes in magnetic coordinates

磁気座標系を用いたゆるやかな平衡変化を含んだ相対論的案内中心方程式

松山 顕之; 矢木 雅敏

Matsuyama, Akinobu; Yagi, Masatoshi

Guiding-center equations for relativistic particles are presented in axisymmetric toroidal geometry using Boozer coordinates. Effects of slow equilibrium change are included for describing the electron acceleration due to the induction field, which is a fundamental process of the runaway electron generation during disruptions. For a consistent treatment of the runaway orbit in finite pressure plasma, the equations are given in both canonical and noncanonical forms with retaining the radial covariant component of the equilibrium magnetic field. For this, the Lagrangian formulation by White and Zakharov is applied to axisymmetric equilibria with slowly-varying magnetic flux functions.