发表机构
State Key Laboratory of Nuclear Physics and Technology, Peking University; Institute of Theoretical Physics, Chinese Academy of Sciences; College of Physics, Sichuan University; Beijing Laser Acceleration Innovation Center（北京大学核物理与技术国家重点实验室; 中国科学院理论物理研究所; 四川大学物理学院; 北京激光聚变创新中心）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
该研究通过二维粒子模拟结合自旋相关氘氚聚变模块，发现束流成丝不稳定性可将相对论电子能量耦合至聚变离子驱动氘氚聚变，且能产生各向异性自旋分辨的极化中子发射。
AI 中文摘要
成丝不稳定性通常被认为对聚变等离子体中的快电子输运有害，因为它会增加束流发散度并重新分配沉积的能量。本研究采用二维粒子模拟，并结合自旋相关的氘氚聚变模块，探究成丝是否可将对向传播电子的能量转移至预极化的聚变离子。模拟结果显示，磁丝与纵向感应电场、横向电荷分离电场共同作用，将初始静止的氘核和氚核加速至能发生聚变反应的能量。在所考察的参数范围内，计算得到的中子产额随饱和磁场能量增加而升高。该模型进一步预测了各向异性、自旋分辨的中子发射，最大中子极化方向近似垂直于主导的氘氚碰撞方向，并随反应离子的角分布演化。这些结果表明，束流成丝可将相对论电子能量耦合至聚变离子，且极化中子发射可作为反映 underlying 等离子体动力学的反应加权特征。
英文摘要
Filamentation instabilities are generally regarded as detrimental to fast-electron transport in fusion plasmas because they increase beam divergence and redistribute deposited energy. Here, we use two-dimensional particle-in-cell simulations coupled to a spin-dependent deuterium-tritium fusion module to investigate whether filamentation can instead transfer energy from counterstreaming electrons to prepolarized fusion ions. The simulations show that magnetic filaments, together with longitudinal inductive and transverse charge-separation electric fields, accelerate initially stationary deuterons and tritons to energies at which fusion reactions occur. Over the parameter range examined, the calculated neutron yield increases with the saturated magnetic-field energy. The model further predicts anisotropic, spin-resolved neutron emission. The direction of maximum neutron polarization is approximately perpendicular to the dominant deuterium-tritium collision direction and evolves with the angular distribution of the reacting ions. These results suggest that beam filamentation can couple relativistic-electron energy to fusion ions and that polarized neutron emission may provide a reaction-weighted signature of the underlying plasma dynamics.
