Controlled Experiment of Relaxation Processes of Many-Particle System Using Strongly Magnetized Nonneutral Plasma

强磁化非中性等离子体多粒子系统弛豫过程的控制实验

• 批准号: 13308021
• 负责人: KIWAMOTO Yasuhito
• 金额: $ 32.03万
• 依托单位: Kyoto University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (A)
• 财政年份: 2001
• 资助国家: 日本
• 起止时间: 2001 至 2003
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-13308021/
• 关键词: Pure electron plasma; Nonneutral plasma; Vortex dynamics; Self-organization; Relaxation of many-particle system with long-range force; Thermal equilibrium plasma

Collective interactions among particles of strongly magnetized pure electron plasma appear as vortex motion. The phenomena that string-shaped high-density groups (clumps) of electrons form highly symmetric arrays have been coined "vortex crystal formation" and attracting much attention as a representative example of self-organization processes. In spite of high academic curiosity, the physical mechanism leading to the ordered states is far from full understanding. The purpose of this project is to physically explore each stage of the self-organization process on one hand and to build an instrumental and methodical basis for next generation of experimental studies by employing strong magnetic field on the other.Major steps toward physical understanding consist of three achievements : (1) Bifurcation between merger and closely-separated states of clumps is found to critically depend on the depth and width of the depletion belt self-generated in the background distribution between the clu … More mps. [Soga, Phys. Plasmas 2003] (2) The background populations curb the clumps' orbital motion, guide them to symmetric configurations and eventually keep them at the crystal lattice. [Sanpei, Phys. Rev. E (2003)] (3) Application of a rotating wave field to a distribution of magnetized electrons leads to a substantial compression of the density distribution when the dispersion of the wave satisfies the radical boundary conditions imposed by the conducting wall and the plasma density profile. However the matching condition includes self-adjustment of the density profile and resonance broadening, suggesting another type of self-organization of the plasma coupled with external fields. [Soga, JPFR-SR6 2004]A new plasma trap operatable with strong magnetic filed up to 2.2T is constructed together with the installation of a newly developed optical transfer system for observation of fine structures in the electron density distribution from a weal magnetic field zone.[Aoki, JJAP 2004] It has been successfully observed that finer structures are generated under the higher magnetic field. The Malmberg trap configuration, best suited to vortex experiments, has not shown confinement time longer than 200s. The Mohri trap configuration, suited to generate Penning type equilibria, has led to the confinement time exceeding500s. The long confinement time is the basis for the advanced study of relaxation toward equilibrium or transition between equilibrium states. This program has successfully prepared the starting point for the next generation of experimental studies of relaxation. Less

强磁化纯电子等离子体中粒子间的集体相互作用表现为涡旋运动。弦状的高密度电子群（团）形成高度对称的阵列的现象被称为“涡旋晶体形成”，并作为自组织过程的代表性例子而引起广泛关注。尽管有很高的学术好奇心，导致有序状态的物理机制还远未完全理解。该项目的目的是一方面从物理上探索自组织过程的每个阶段，另一方面为下一代利用强磁场进行的实验研究建立仪器和方法基础。物理理解的主要步骤包括三个成果：（1）团簇的合并态和紧密分离态之间的分歧主要取决于耗尽带的深度和宽度。在背景中生成的分布在各分支之间， ...更多信息 mps [Soga（2）背景粒子数抑制了团块的轨道运动，将它们引导到对称构型，并最终将它们保持在晶格中。[Sanpei，Phys.Rev.E（2003）]（3）当波的色散满足由导电壁和等离子体密度分布施加的自由基边界条件时，将旋转波场应用于磁化电子的分布导致密度分布的实质压缩。然而，匹配条件包括自调整的密度分布和共振加宽，这表明另一种类型的自组织的等离子体与外部场耦合。[Soga在2.2T强磁场下，构造了一个新的等离子体阱，并安装了新研制的光学传输系统，用于观测弱磁场区电子密度分布的精细结构。[Aoki，JJAP 2004]已经成功地观察到，在更高的磁场下产生更精细的结构。Malmberg阱配置，最适合于旋涡实验，没有显示约束时间超过200秒。Mohri阱结构适合于产生Penning型平衡，其约束时间超过500 s。长约束时间是进一步研究弛豫向平衡态或平衡态之间转变的基础。该计划成功地为下一代放松实验研究奠定了基础。少

项目成果

Y.Soga, Y.Kiwamoto, A.Sanpei, J.Aoki: "Merger and binary structure formation of two discrete vortices in a background vorticity distribution of a pure electron plasma"Phys.Plasmas. Vol.10,No.10. 3922-3926 (2003)

Y.Soga、Y.Kiwamoto、A.Sanpei、J.Aoki：“纯电子等离子体背景涡度分布中两个离散涡流的合并和二元结构形成”Phys.Plasmas。

Y.Kiwamoto, A.Sanpei, Y.Soga, J.Aoki, Y.Yatsuyanagi, T.Ozawa: "Critical Contribution of Low-Density Background Particles in the Formation of Ordered Structures in a Pure Electron Plasma"J.Plasma and Fusion Research SERIES. Vol.6. 8 (2004)

Y.Kiwamoto、A.Sanpei、Y.Soga、J.Aoki、Y.Yatsuyanagi、T.Ozawa：“低密度背景粒子对纯电子等离子体中有序结构形成的关键贡献”J.Plasma and Fusion

A.Sanpei, Y.Kiwamoto, K.Ito, Y.Soga: "Formation of a Vortex Crystal Cell Assisted by a Background Vorticity Distribution"Physical Review E. 68, No.1-2. 016404

A.Sanpei、Y.Kiwamoto、K.Ito、Y.Soga：“背景涡量分布辅助下涡旋晶体单元的形成”物理评论 E. 68，No.1-2。

際本泰士: "「プラズマの生成と診断」の中で7・3節「非中性プラズマ」を分担"コロナ社(プラズマ核融合学会編). 433-440 (2004)

Yasushi Saimoto：“《等离子体生成和诊断》中的第 7.3 节“非中性等离子体””Coronasha（由等离子体融合协会编辑）433-440 (2004)。

Y.Kiwamoto, K.Ito, A.Sanpei, Y.Soga: "Bifurcation in the Evolution of Vortex Structure in a Magnetized Pure Electron Plasma"Bifurcation Phenomena in Plasmas (Kyushu University Press ISBN 4-9901142-5-6). 114-127 (2002)

Y.Kiwamoto、K.Ito、A.Sanpei、Y.Soga：“磁化纯电子等离子体中涡旋结构演化中的分岔”等离子体中的分岔现象（九州大学出版社 ISBN 4-9901142-5-6）。