Development of a supersonic beam of metastable He atoms for electric field measurements in magnetically confined plasma edges

开发亚稳态 He 原子超音速束，用于磁约束等离子体边缘的电场测量

• 批准号: 14580518
• 负责人: TAKIYAMA Ken
• 金额: $ 1.98万
• 依托单位: HIROSHIMA UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2002
• 资助国家: 日本
• 起止时间: 2002 至 2003
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-14580518/
• 关键词: Plasma diagnostics; Electric field measurement; Metastable He atoms; Atomic He beam; Laser-induced fluorescence; Penning discharge; レーザー誘起蛍光

Electric fields E induced in plasma edges play an essential roll in plasma confinement. We have developed a high sensitive laser-induced fluorescence method to measure E in plasmas by using the Stark effect of He atoms. For plasmas that does not contain He gas, this method, however, has to be combined with a neutral He beam probe. Purpose of this work is to develop a short pulsed, compact supersonic He beam with a sufficient density of metastable He (2^1S) atomsPulsed atomicbeam source that consists of a fast acting valveand a skimmer was developed The beam characteristics were measured with a fashion gauge under the various conditions and compared with calculations using a simple model that took into account interaction between the beam and gas in the region between nozzle and skimmer. From the results we found the optimum condition to generate a high-quality supersonic pulsed beam in the case of compact beam source. For a 0.2 ms pulse, a beam of density n 【less than or equal】 5.4x10^<13> cm^<-3>, velocity ν 〓 1.7 km/s and a beam width D 〓 4 mm at 20 cm from the skimmer was achievedHe atoms in the beam were successfully excited and ionized by using a Penning type discharge. Spectroscopic investigation showed that the discharge produced plasmas with a relatively high temperature and the temperature was strongly dependent upon the discharge voltage Future work is to measure the density of metastable atoms generaed in the discharged beam to elucidate thecorrelation between the density and discharge conditions

等离子体边缘产生的电场在等离子体约束中起着至关重要的作用。利用He原子的Stark效应，建立了一种高灵敏度激光诱导荧光测量等离子体中E的方法。然而，对于不含He气体的等离子体，这种方法必须与中性He束探针结合使用。本文的目的是研制一种具有足够亚稳He （2^1S）原子密度的短脉冲、紧凑的超音速He束。研制了一种由速动阀和撇油器组成的脉冲原子束源。用一种流行计测量了不同条件下的光束特性，并与考虑光束与喷嘴和撇油器之间区域气体相互作用的简单模型计算结果进行了比较。从结果中找到了在紧凑光束源下产生高质量超音速脉冲光束的最佳条件。在0.2 ms脉冲下，获得了密度n≤5.4 × 10^<13> cm^<-3>的光束，速度ν = 1.7 km/s，距离撇光器20 cm处的光束宽度D = 4 mm。光谱学研究表明，放电产生的等离子体具有较高的温度，且温度与放电电压密切相关。未来的工作是测量放电光束中产生的亚稳原子密度，以阐明密度与放电条件之间的关系

项目成果

K.Takiyama: "A Metastable Helium Beam by a Penning Discharge for Measurement of Electric Field in Plasmas"The 56th annual Gaseous Electronics Conference, San Francisco, CA, Oct.21-24,2003,Bull.Amer.Phys.Soc.. 48・6. 46 (2003)

K.Takiyama：“通过彭宁放电测量等离子体电场的亚稳态氦束”第 56 届年度气体电子会议，加利福尼亚州旧金山，2003 年 10 月 21-24 日，Bull.Amer.Phys.Soc.。 48・6。46（2003）

K.Takiyama: "High-Sensitive LIF Measurements of Electric Field Perpendicular to Magnetic Field in Plasmas"Proc.11th Int.Sympo.Laser-Aided Plasma Diagnostics, Les Houch, France, Sept.29-Oct.2,2003. (計5頁). (2003)

K.Takiyama：“等离子体中电场垂直于磁场的高灵敏度 LIF 测量”Proc.11th Int.Sympo.Laser-Aided Plasma Diagnostics，法国 Les Houch，2003 年 9 月 29 日至 10 月 2 日 (5.页）（2003）。

K.Takiyama: "High-Sensitive LIF Measurements of Electric Field Perpendicular to Magnetic Field in Plasmas"Proc.11th Int.Sympo.Laser-Aided Plasma Diagnostics, Les Houch, France, Sept.29-Oct.2, 2003. CD-ROM. (2003)

K.Takiyama：“等离子体中电场垂直于磁场的高灵敏度 LIF 测量”Proc.11th Int.Sympo.Laser-Aided Plasma Diagnostics，Les Houch，法国，2003 年 9 月 29 日至 10 月 2 日。CD-

K.Takiyama: "High-Sensitive LIF Measurements of Electric Field Perpendicular to Magnetic Field in Plasmas"Proc.11th Int.Sympo.Laser-Aided Plasma Diagnostics, Les Houch, France, Sept.29-Oct.. 2. 5 (2003)

K.Takiyama：“等离子体中电场垂直于磁场的高灵敏度 LIF 测量”Proc.11th Int.Sympo.Laser-Aided Plasma Diagnostics，Les Houch，法国，9 月 29 日至 10 月 2. 5 日（2003 年）

P.X.Feng: "High-density metastable helium atoms produced by Penning-type discharges"Plasma Sources Sci.Technol.. 12. 142-147 (2003)

P.X.Feng：“潘宁型放电产生的高密度亚稳态氦原子”Plasma Sources Sci.Technol.. 12. 142-147 (2003)