Production of Multiply-Charged Ions of Ne, Ar, Kr and Xe by the Electron-Bonbarded Hot Cathode IoN Source of IPCR

Production of multiply-charged ions of Ne, Ar, Kr and Xe has been studied by use of an electron-bombarded hot cathode type ion source of the IPCR 160cm cyclotron, which is similar to Morozov's source. These multiply-charged ions were accelerated by a 3rd harmonics acceleration mode in the cyclotron and detected with a beam probe fixed at the radius of 55cm. Observed multiply-charged ions are Ne2+, Ne3+, Ne4+, Ne5+, Ar3+, Ar4+ Ar5+, Ar6+, Ar7+, Ar8+, Kr6+, Kr7+, Kr8+, Kr9+, Xe9+, Xe10+ and Xe11+. Relative abundance of each charge state of four elements were measured. In case of Kr and Xe , the intensity of observed multiply-charged ions decreased to 1/3 or 1/4 when the charge number is increased by one. Intensities of Ar4+, Ar6+, Ar8+, Kr6+ and Kr8+ were measured as a function of the operation conditions of the ion source, such as arc voltage, arc power and gas flow rate. It was found that a smaller gas flow and a higher arc power brought about a higher yield in all the measured ions. Obtained current intensities of ion source output are 40?A Ar8+, 600?A Kr6+, 40?A Kr9+, 150?A Xe9+ and 10?A Xe11+ respectively.     

The Production and Acceleration of Metal Ions in the Harwell Variable Energy Cyclotron

The range of ions accelerated by the V.E.C. has recently been extended to metal ions. For example, a 5 to 10 ?A beam of 48 MeV 58Ni6+ is now available and has been used by a customer. This beam has become possible as a result of success in adapting the normal ion source for the production of metal ions. The problem was to add to the ion source a controlled source of metal vapour without increasing the size of the ion source or adding separate oven heaters and controls. This has been achieved by inserting a graphite liner into the existing ion source chimney, the metal being embedded in the liner and out of direct contact with the arc. Provided the arc power exceeds a few kilowatts, the metal becomes molten and the vapour diffuses through the graphite into the arc which then becomes self-sustaining. With nickel (the most widely tested so far), intensity at full radius of between 10 and 20 ?A of 6+ ions and 1?A of 8+ ions is readily obtained and source life averages about 4 hours. Other metals such as cobalt, iron, chromium and copper give similar results.     

Hot Cathode’s Working Voltage Impacts on the Operation of High Current Ion Source

High power ion source is one of the important parts of the neutral beam injection. It produces high energy beam by extracting and accelerating ions from its arc chamber. The hot cathode (filaments) in the arc chamber of the ion source operates in two modes. Operation mode of the cathode has great effect on the stable operation of the ion source. Based on the theory of hot cathode and experimental results, this paper presents the operation results (beam current, arc efficiency) of an ion source with various cathode temperatures (controlled by voltage applied to the cathode).     

Analysis of Effects of the Arc Voltage on Arc Discharges in a Cathode Ion Source of Neutral Beam Injector

A hot cathode bucket ion source is used for the EAST(experimental advanced superconducting tokamak)neutral beam injector.The thermal electrons emitted from the surface of the cathode are extracted and accelerated by the electric field formed by the arc voltage,which is applied between the arc chamber of the ion source and the cathode.This paper analyzes the effects of arc voltage on the arc discharge in a hot cathode high current ion source.     

Heavy Ion Acceleration at Cyclone (Belgium)

CYCLONE is an isochronous cyclotron in operation in Louvain-la-Neuve (Belgium). It is equipped with a P. I. G. hot cathode heavy ion source and accelerates various ions up to energies of 110 MeV Q2/A with extracted beam intensities reaching 10 ?A in the 4+ state. The source is described and some performance parameters are given. In order to reach higher charge states an injector cyclotron is projected which will allow a final energy of 27 MeV/nucleon up to neon decreasing to 6 MeV/nucleon for xenon. Extracted intensities vary between 5 × 1013 and 109 pps depending on particle and energy. Some design aspects are described which will allow the cost of the project to be quite low.     

Characteristics of a Cold Cathode Type Penning Source and Low Energy Isotope Separation of High Charge States

Measurements of voltage-, current-and gas flow dependencies of a cold cathode Penning source, using different cathode materials, are reported. The influence of the discharge parameters (arc voltage, arc current, magnetic field and gas flow) on the production of higher charge states was studied. The highest observed charge states were Ar9+ , Kr12+ Xe13+ The cold cathode type Penning source with radial extraction proves to have sufficiently low energy spread to permit isotope separation in the source-magnet field. Results for Ar2+, Kr4+ and Xe7+ as well as emittance measurements are given.     

Duoplasmatron Ion Sources

A survey on questions related to the production of multiply charged ions with the Duoplasmatron ion source is given. In spite of differences of the multiply charged ion source and the mass separator type, design considerations show that high containment is a common feature to be attained in both subjects. Multiply charged metal ions are produced by material evaporation into the magnetically confined anodic plasma and auxiliary gas feed into the cathode discharge regions. Energy spreads of ion beams from the low and the high arc current source are compared. The Duoplasmatron ion source proves to be a hygieneous source of high containment that permits the production of medium charge states up to 9+ for xenon at modest energy spread and good brilliance of the extracted ion beam in a high current-low voltage discharge mode.     

氧负离子潘宁源的实验研究

文章涉及用袖珍永磁潘宁源产生毫安级氧负离子束的实验研究。给出了磁场、不同阴极材料及源的离子发射孔对引出氧负离子束的影响。目前,该类型离子源已成功地用于正负氧离子同时加速的1MVISR RFQ加速器上。     

碳团簇及C60负离子的产生

利有铯负离子溅射源和石墨阴极产生并引出了碳团簇负离子流，观察到了一些电子亲和势很小的团簇，用Ｃ６０／Ｃ７０混合物做阴极，也引出了Ｃ６０及其碎片的负离子束，分析了碳团簇负离子束流的质谱组成特点和束流变化的一些规律。     

The ORNL ECR multicharged ion source

A multicharged ion source based on electron cyclotron resonance (ECR) heating has been designed and built at ORNL. The ECR ion source, which is completely dedicated for atomic physics collisions studies, produces higher charge states and higher beam intensities than the present ORNL PIG multicharged ion source, and will thus permit study of collision processes involving ions of higher charge states in experiments requiring higher beam intensities than could be previously obtained in our laboratory. The source has already produced up to fully stripped C and O beams, as well as up to He-like Ar beams. Measurements of the energy spread of ions extracted from the ion source operating in both single-stage and two-stage mode are described. In addition, initial results of total cross section measurements for fully stripped light ions incident on atomic hydrogen in the energy range 0.2–10 keV are presented.     

阴极端面旋转弧根的数值分析

辅助电弧的阴极弧根在管状钨阴极端面旋转时，随着阴极弧根旋转频率的增加，在阴极端面形成一圈温度较高的区域；区域中各点的温度（除弧根处温度）趋于均匀，从而为主电弧的阴极弧根在这个区域中分裂成多弧根或形成扩散型弧根模式提供了必要的温度条件；弧根处的阴极端面温度随旋转频率的增加而下降并趋于一个稳定的值。本文利用三维热传导方程对此进行了分析。     

A Small "Cold-Cathode" High-Intensity Cyclotron Ion Source

High beam currents have been achieved with a radial source which fits into the 2-inch gap of a 30-inch cyclotron. The geometry is that of a cold-cathode or P. I. G. source. However, the cathodes are heated to thermionic temperatures by ion bombardment rather than a conventional high-current heated filament. The source is now in use and produces intense beams of H+, D+, He3, and alpha particles. Internal beams of H+ or D+ of more than one mA are obtained routinely at extraction radius. In addition, 30 ?A of H- or D- are obtained at a stripping foil by merely reversing the magnetic field of the cyclotron.     

低能高束流氩离子源的结构及性能

离子源技术是等离子体研究中的一项重要内容,而低能大束流源则是离子源技术研究中的一个重要方向,因为这样的源在离子束刻蚀、离子束溅射镀膜以及荷能粒子与物质相互作用方面都有广泛的应用;本文采用空心阴极空心阳极结构,用热阴极电子发射弧放电驱动并用磁场约束产生等离子体,用曲面发射引出离子束,研制成了氩气放电溅射离子源;研究了灯丝加热电流、弧压对弧流的影响和弧流与工作气体压力对离子束引出的影响规律.离子源的引出电压在0-4.0 kV之间连续可调,最大引出束流为100 mA,束斑面积为φ6.0 cm,以Ti为溅射靶时的最大溅射沉积率为0.45 nm/s,离子源可连续工作160 h.     

袖珍永磁端引出PIG离子源

介绍了一个袖珍永磁端引出ＰＩＧ离子源，它可用于产生各种气体的单电荷和多电荷离子，在不大于３０Ｗ的放电功率下，可引出ｍＡ级离子流，源的阴极寿命大于２００ｈ。     

真空弧离子源脉冲工作瞬间的放电行为

采用高速摄影和光谱诊断的方法研究了真空弧离子源脉冲工作瞬间的放电行为。拍摄了离子源放电瞬间吸氢电极上阴极斑的形成过程，分析了不同放电电流时阴极斑的发射光谱。实验结果表明，当脉冲工作电流为10^1—10^2A时，真空弧离子源放电区一般只有单个阴极斑，阴极斑的位置在同一次放电中的变化很小；较大的脉冲工作电流有利于提高阴极斑的温度，并最终导致氢离子浓度的增加，但也会使阴极材料的溅射更加严重，造成离子源等离子体品质下降。     

钨掺杂的提铯离子筛的制备及离子交换性能研究

以ZrOCl₂、Na₂MoO₄、Na₂WO₄、K₄P₂O₇为原料,通过沉淀反应、Cs⁺嵌入、固位、抽出等一系列程序合成了用于提取铯的钨掺杂离子筛(W-Cs-IS),研究了W的掺杂比例对离子筛Cs⁺交换性能的影响。用X射线光电子能谱（XPS）、扫描电子显微镜（SEM）及能谱分析（EDS）、氮气吸附-解吸等手段表征了产物的微观结构,并测试了其耐酸性。结果表明：掺杂的W部分存在于产物表面,Mo包藏于内部;离子筛由不规则颗粒及膜状部分组成,具有微孔结构,微孔尺寸约为20 nm;在HCl和HNO₃中均显示出良好的耐酸性。W掺杂有利于提高离子筛的交换性能。随着掺杂比例的增加,离子交换容量先提高后基本不变,在中性（pH=6.98）和酸性（pH=1.05）条件下分别可达到1.66 mmol/g和1.47 mmol/g。W-Cs-IS对模拟高放废液中的Cs⁺和Sr²⁺具有较高的选择性,可同时将Cs⁺和Sr²⁺从高放废液中提取出,对模拟高放废液中Cs⁺的提取率可达到88.2%。     

Use of the Hot-Electron Mirror Machine Interem as a High-Z Ion Source

Production of the high-Z charge states in helium, nitrogen, and argon has been measured in the INTEREM device at the Oak Ridge National Laboratory. The INTEREM device contains a hot electron (~500 keV) plasma trapped in a minimum B geometry. The device is of interest because its parameters, electron density and energy, and ion lifetime are consistent with those required for the production of highly charged ions. Ion charge and ion energy spectra were measured independently using an einzel lens type energy analyzer combined with a quadrupole mass filter. For helium, most of the ions were doubly charged under proper operating conditions. For nitrogen, we found the ion yield to be peaked at Q = 4, and under these conditions the yield at Q = 6 was down by a factor of about 20. Energy distribution curves for different charge states show interesting features, from which important information may be inferred about the plasma in INTEREM. Although discrepancies exist in the ion yields we conclude that an INTEREM-like device employing a minimum B geometry and electron cyclotron resonance heating may be expected to be a good high-Z ion source.     

Study the Characteristic of the Hot Cathode of High Current Ion Source

The difference of hot cathode operation mode has great influence on the arc discharge of high current ion source. Based on the analysis of the theory of hot filament with two operation modes and combined with ion source experiments, the paper studies the effects of hot filament operation modes on ion source arc discharge.     

Investigation of Arc Regulation of Hot Cathode Ion Source with Langmuir Probe

The neutral beam injector (NBI) is one of the main plasma heating methods for nuclear fusion devices. For the hot cathode high current ion source, the arc current and beam current tends to increase during the beam pulse. In order to gets long pulse beam extraction, the arc regulation technology is employed. The Langmuir probes are installed on the experimental advanced superconducting tokamak-NBI ion source, to feedback control the arc discharge and beam extraction. The experimental results show that, the long pulse of 100 s ion beam is extracted with beam energy of 30 keV with arc regulation. More the results are presented in this paper.