A purely magnetic applied field may provide plasma confinement under conditions where the bulk of the plasma is effectively free of the applied magnetic field. The applied magnetic field surrounds the bulk of the plasma, and plasma particles that are incident on the applied magnetic field can be reflected back into the effectively unmagnetized region of plasma. The concept belongs to a class of magnetic plasma confinement approaches studied long ago, for which some experimental results indicated that classical (collision-based) cross-magnetic-field transport may occur. However, multiple magnetic coils are required to be immersed within the confined plasma, and rapid plasma loss may occur if material structures are present, which pass through the plasma (e.g., to hold the immersed coils in place). In the work reported, the concept is studied in combination with magnetic plasma expulsion [R. E. Phillips and C. A. Ordonez, Phys. Plasmas 25, 012508 (2018)], which would be employed to keep plasma away from material structures that pass through the plasma. A planar model is used for the study. A classical trajectory Monte Carlo simulation is carried out on particles that are independently incident on the applied magnetic field. With monoenergetic incident particles, the results indicate that the applied magnetic field can reflect all independently incident particles in certain regions of parameter space. Prospects for achieving three-dimensional magnetic confinement of an effectively unmagnetized plasma with a Maxwellian velocity distribution are discussed.

中文翻译：

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有效未磁化等离子体粒子的磁约束

在大部分等离子体有效地不受外加磁场影响的条件下，纯磁场外加场可以提供等离子体限制。外加磁场围绕着大部分等离子体，入射到外加磁场上的等离子体粒子可以被反射回等离子体的有效未磁化区域。该概念属于很久以前研究过的一类磁等离子体约束方法，一些实验结果表明可能会发生经典的（基于碰撞的）交叉磁场传输。然而，需要将多个磁线圈浸入受约束的等离子体中，如果存在穿过等离子体的材料结构（例如，将浸入的线圈固定到位），则可能发生快速的等离子体损失。在报道的工作中，该概念是结合磁性等离子体排出进行研究的 [RE Phillips 和 CA Ordonez, Phys. Plasmas 25, 012508 (2018)]，这将用于使等离子体远离穿过等离子体的材料结构。平面模型用于研究。经典轨迹蒙特卡罗模拟是对独立入射到外加磁场的粒子进行的。对于单能入射粒子，结果表明外加磁场可以反射参数空间某些区域中所有独立入射的粒子。讨论了实现具有麦克斯韦速度分布的有效未磁化等离子体的三维磁约束的前景。这将用于使等离子体远离穿过等离子体的材料结构。平面模型用于研究。经典轨迹蒙特卡罗模拟是对独立入射到外加磁场的粒子进行的。对于单能入射粒子，结果表明外加磁场可以反射参数空间某些区域中所有独立入射的粒子。讨论了实现具有麦克斯韦速度分布的有效未磁化等离子体的三维磁约束的前景。这将用于使等离子体远离穿过等离子体的材料结构。平面模型用于研究。经典轨迹蒙特卡罗模拟是对独立入射到外加磁场的粒子进行的。对于单能入射粒子，结果表明外加磁场可以反射参数空间某些区域中所有独立入射的粒子。讨论了实现具有麦克斯韦速度分布的有效未磁化等离子体的三维磁约束的前景。经典轨迹蒙特卡罗模拟是对独立入射到外加磁场的粒子进行的。对于单能入射粒子，结果表明外加磁场可以反射参数空间某些区域中所有独立入射的粒子。讨论了实现具有麦克斯韦速度分布的有效未磁化等离子体的三维磁约束的前景。经典轨迹蒙特卡罗模拟是对独立入射到外加磁场的粒子进行的。对于单能入射粒子，结果表明外加磁场可以反射参数空间某些区域中所有独立入射的粒子。讨论了实现具有麦克斯韦速度分布的有效未磁化等离子体的三维磁约束的前景。