环形等离子体中静电涨落引起的混沌输运
Chaos-induced transport due to electrostatic-fluctuations in a toroidal plasma
- Instituto de Ciencias Nucleares, UNAM（墨西哥国立自治大学核科学研究所）
- Institute for Fusion Studies, UT Austin（德克萨斯大学奥斯汀分校聚变研究中心）
机构由 AI 辅助整理，请以论文原文为准。
AI总结：
本文通过环形几何中的试验粒子模型，研究静电涨落引起的混沌输运，发现混沌运动与随机过程均导致扩散输运，且带状流可形成输运垒，支持混沌运动为输运机制。
AI中文摘要：
采用环形几何中的试验粒子模型研究了由静电涨落产生的等离子体输运。假设了一个模型波谱，该波谱在强磁场中粒子运动的哈密顿描述中引入了时间依赖性。这允许存在混沌粒子运动，从而产生输运过程。产生输运的另一种方式是在波谱内引入随机过程。探讨了这两种可能性，并表明两种情况都会产生扩散输运。通过计算近似李雅普诺夫指数证实了混沌运动的存在。此外，还考虑了带状流的存在，在表现出混沌输运的情况下，带状流可通过抑制径向粒子通量而产生输运垒。这一效应支持了混沌运动是输运原因的观点，因为它再现了在混沌的哈密顿模型中观察到的鲁棒不变环面对混沌的抵抗行为，该不变环面充当输运垒。
英文摘要：
Plasma transport produced by electrostatic fluctuations is studied using a test particle model in a toroidal geometry. A model wave spectrum is assumed which introduces a time dependence in the Hamiltonian description of particle motion in the strong magnetic field. This allows for the existence of chaotic particle motion which gives rise to transport processes. Another way of producing transport is by introducing a stochastic process inside the wave spectrum. The two possibilities are explored and it is shown that both cases give rise to diffusive transport. The presence of chaotic motion is corroborated by computing approximate Lyapunov exponents. Additionally the presence of zonal flow is considered which can give rise to a transport barrier by suppressing radial particle fluxes, in the cases that show chaotic transport. This effect gives support to the existence of chaotic motion as responsible for transport since it reproduces the behavior of the robust invariant torus resilience to chaos, acting as a transport barrier, observed in Hamiltonian models of chaos.
