发表机构
São Paulo State University (UNESP); Institute of Geosciences and Exact Sciences; University of São Paulo; Institute of Physics; Federal University of Paraná（圣保罗州立大学; 地球科学与精确科学学院; 圣保罗大学; 物理研究所; 巴拉那联邦大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本文提出一种无场台球，通过边界几何重现磁镜的绝热约束机制，发现约束强度随轮廓长度非单调变化，并在中间长度达到最强，且逃逸方向对初始条件高度敏感。
AI 中文摘要
我们引入了一种无场、无外力的台球系统，通过边界几何形状重现磁镜的绝热约束机制。快速横向反射产生一个近似守恒的作用量，该作用量扮演磁矩的角色，从而形成有效的纵向势垒和标称的逃逸损失锥。对于此处考虑的半宽轮廓，约束由镜强度和绝热性之间的竞争控制：缩短轮廓会增加镜比，但同时降低绝热近似的精度。因此，逃逸分数是非单调的，约束在中间轮廓长度处最强。我们刻画了相关的相空间结构、逃逸时间统计和逃逸盆地，揭示了长寿命的瞬态运动以及最终逃逸方向对初始条件的强烈敏感性，这种敏感性在初始条件不确定性减小时依然存在。
英文摘要
We introduce a stationary, field-free billiard that reproduces the adiabatic confinement mechanism of a magnetic mirror through boundary geometry alone. Rapid transverse reflections generate an approximately conserved action that plays the role of the magnetic moment, producing an effective longitudinal barrier and a nominal loss cone for escape. For the half-width profile considered here, confinement is controlled by a competition between mirror strength and adiabaticity: shortening the profile increases the mirror ratio but also reduces the accuracy of the adiabatic approximation. As a result, the escaping fraction is nonmonotonic and confinement is strongest at an intermediate profile length. We characterize the associated phase-space structure, escape-time statistics, and escape basins, revealing long-lived transient motion and a strong sensitivity of the final escape direction to the initial condition that persists as the uncertainty in the initial condition is reduced.
