Research and Development of a High Current Deuterium Negative Ion Source

高电流氘负离子源的研制

基本信息

批准号：
02452277
负责人：
FUKUMASA Osamu
金额：
$ 3.65万
依托单位：
Yamaguchi University
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (B)
财政年份：
1990
资助国家：
日本
起止时间：
1990 至 1991
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-02452277/
关键词：
NBI heating volume production type negative ion source double plasma type negative ion source H^-D^- production vibrationally excited hydrogen molecules dissociative attachment magnetic filter plasma grid H^-D^-生成バケット型負イオン源電子エネ

项目摘要

High current hydrogen/deuterium negative ion sources are of interest to the fusion community for the preparation of neutral beams, namely NBI heating of fusion plasmas. To this end, basic processes for enhancement of H^- production and H^- extraction in volume sources have been studied experimentally, theoretically and computationally (i. e. particle simulation).(1) The role of fast electrons e_f in H^- production processes is well clarified theoretically. Vibrational molecules H_2^*, are essential to H^- production. Among some production processes of H_2^*, the collisional excitation of H_2^* by e_f is most important to enhance the H^- yield.(2) Relationship between extraction of H^- ions optimized by plasma grid potential and plasma parameters in a bucket source is clarified experimentally.(3) A double plasma type negative ion source is newly designed. In this source, the energy distribution of e_f and its quantity are well controlled by changing the potential difference between two plasmas. Volume production of H^- ions caused by the so-called two step process is well confirmed experimentally.(4) Two dimensional electrostatic particle simulation is implemented to study energy dependent electron transport across a magnetic filter, and to study extraction of H^- ions.(5) Deuterium plasmas are well produced, and volume produced D^- ions are extracted. Isotope effects are now under study.

融合束的制备，即NBI加热融合等离子体，高电流/氘负离子源对融合群落的准备很感兴趣。为此，已经在实验，理论上和计算上研究了体积源中H^ - 产生和提取H^ - 提取的基本过程（即粒子模拟）。（1）理论上很好地阐明了快速电子E_F在H^ - 生产过程中的作用。振动分子H_2^*，对于H^ - 生产至关重要。在H_2^*的某些生产过程中，E_F对H_2^*的碰撞激发对于增强H^ - 产量最重要。（2）（2）通过等离子体网格电位优化的H^ - 离子的提取之间的关系是桶源中的血浆参数，实验中阐明了桶源。在此源中，通过改变两个等离子体之间的电势差，可以很好地控制E_F及其数量的能量分布。由所谓的两个步骤引起的H^ - 离子的体积产生在实验中得到充分证实。（4）实施了二维静电颗粒模拟，以研究跨磁过滤器的能量依赖性电子传输，并研究提取H^^ions。（5）氘等质量的生产良好，并产生了d^ - 离子的d^ - 离子。同位素效应现在正在研究中。