Phase Space Studies of Ion Energization in Laboratory Plasmas

在历史上，对等离子体的研究主要集中在等离子体中带电粒子、离子和电子的平均性质的演变，即等离子体的密度、流动和温度。在这个项目中，离子和电子的详细运动将在重现空间中自然发生的过程的条件下进行研究，或者在实验室磁化等离子体实验中在等离子体和墙壁之间的界面上进行重现。对空间中离子和电子速度分布函数的现场测量使空间物理领域发生了革命性的变化，使空间物理界能够研究和理解动力学尺度过程；测试理论和计算模型；并发现新的等离子体现象。通过对离子速度分布函数的详细测量，该小组将确定观察到的离子热各向异性与实验室等离子体中等离子体热压力与磁压之比之间的逆关系是否与离子回旋或离子镜不稳定阈值的理论预测一致。除了拟议的研究可能对理解等离子体中的离子能化做出的科学贡献外，这项工作的更广泛影响涉及在强调基础等离子体物理和应用等离子体物理之间的协同作用的研究环境中对研究生进行培训。这项工作的基础设施进步影响是开发了一种新型激光诊断技术，用于测量低温等离子体中的瞬变和稳态磁场。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Historically, the study of plasmas has focused on the evolution of the average properties of the charged particles in the plasma, the ions and electrons, i.e., the density, flow, and temperature of the plasma. In this project, the detailed motion of both ions and electrons will be investigated under conditions that reproduce processes that occur naturally in space or at the interface between plasmas and walls in laboratory magnetized plasma experiments. The in situ measurement of ion and electron velocity distribution functions in space has revolutionized the field of space physics, providing the space physics community an ability to study and understand kinetic-scale processes; test theories and computational models; and to discover new plasma phenomena. Through detailed measurements of the ion velocity distribution function, the group will determine if the observed inverse relationship between ion thermal anisotropy and the ratio of the plasma thermal pressure to magnetic pressure in laboratory plasmas is consistent with theoretical predictions for the ion cyclotron or ion mirror instability threshold. Beyond the scientific contribution that the proposed research could make to the understanding of ion energization in plasmas, the broader impact of the work involves the training of graduate students in a research environment that emphasizes the synergy between basic and applied plasma physics. The infrastructure advancement impact of this work is the development of a novel laser diagnostic to measure transient and steady-state magnetic fields in a low temperature plasma.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.