医用回旋加速器内部负氢离子源实验

医用回旋加速器使用内部负氢离子源,可简化整机结构,节省造价。回旋加速器工程组基于负PIG离子源的工作原理和现有的实验条件,研制了1台内部负氢离子源,并进行了出束实验,在实验条件受到各种限制的情况下,引出的束流达到了160 μA。     

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。     

高产额中子发生器研制

本文介绍了用于安检辐射成像的高产额中子管及中子发生器装置的主要性能指标和研发设计过程。中子管离子源采用冷阴极潘宁离子源,在引出阴极加磁钢,提高引出离子浓度。离子光学系统采用单电极加速结构,靶端通过外加电阻产生抑制电压,减小靶流,提高中子管工作稳定性。对中子管离子源和靶端通过散热结构设计和利用变压器油进行散热,效果良好。通过对中子管的各项性能参数进行测试,离子流可达50 mA以上,引出束流接近1 mA,中子产额达1.1×10¹⁰s^-1。研发的高产额中子管及发生器装置具有产额高、工作稳定、安全便携等优点,达到了设计目的。     

负氢离子等离子体源

本文叙述了乌克兰科学院物理研究所研制的负氢离子源物理过程的理论与实验研究结果。这是一个带有热阴极和垂直于磁场引出Ｈ＾－离子的反射放电离子源。在理论工作部分，根据给定的阴极电流和电子能量、气体压强及放电几何条件，计算了气体放电的等离子体参数。包括Ｈ＾－离子浓度在内的等离子体参数是在考虑了放电室体积内和表面上的主要碰撞反应后对玻尔兹曼方程进行数值解的基础上确定的。     

15-20mA负氢离子源的设计

制约强流质子回旋加速器技术发展的一个主要因素是离子源的束流强度以及束流品质，为提高引出流强、改善束流品质，中国原子能科学研究院一直致力于离子源的发展。2000年建成了平均流强5．2mA的负氢离子源，束流发射度达到了0．65πnm-mrad，2004年建成了高于10mA的负氢离子源。为进一步提高束流流强，满足中国原子能科学研究院串列加速器升级工程的需求，在原有10mA负氢离子源基础上设计1台新的离子源，将平均引出束流提高到15-20mA。     

反应堆上产生强流放射性核束的模拟实验装置

正研制了一台反应堆上产生强流放射性核束的模拟实验装置。模拟装置示于图1,模拟装置真空室与反应堆中子管道尺寸一致。模拟装置由真空系统、真空室、加热系统、离子源、导向器、四极透镜、束测单元等元件组成。离子源阴极采用LaB6材料,由加热元件加热发射电子,电子在阴极和阳极之间加速获得能量后在阳极内与原子碰撞将原子电离。离子源位于20kV的电位上,离子通过引出电极引出加速获得20keV的能量。紧跟着离子源,布置了一套XY导向器,然后是两组四极     

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。     

边引出永磁PIG离子源的某些进展

引言简易、中流强、多离子种类离子源对于注入机是十分有益的。目前看来经由宋执中等人发展起来的永磁边引出潘宁源,经适当改进后是一可供选择的源型。为此,笔者在此基础上,对源的结构、阴极材料进行了一些变革和试验,现介绍如下。     

表面电离离子源束引出特性

一、引言表面电离离子源在电磁同位素分离器、质谱计、离子发动机、溅射负离子源等装置中得到了广泛的应用。使用表面源(即表面电离离子源)时,总是遇到离子束的束型问题,即表面源的引出特性问题。表面源由于产生离子的机制不同于气体放电离子源,不存在等离子体“弯月面”。离子发射面是电离器表面,它是刚体,不随引出参数和引出束流的变化而变化。因此,用表面源研究透镜效应和束空间电荷的作用是十分有利的。但到目前为止,还未见到对表面源的引出特性作系统的研究。     

强流负氢离子源发射度测量仪研制

在加速器技术研究中，束流发射度是反映束流品质的重要物理参数，也是加速器和束流传输线设计的重要依据。100 MeV回旋加速器采用18 mA强流负氢离子源来产生负氢束，为了准确测量离子源的发射度，研制了一台强流负氢离子源发射度测量仪，介绍了其基本原理、机械设计和实验结果，得到了离子源的发射度信息，为100 MeV回旋加速器的设计提供了发射度参数。     

Transient Behavior of Negative Hydrogen Ion Extraction from Plasma

For plasma source,the extraction of negative ions is quite diferent from that of positive ions.To understand the efect of extraction field on plasma,the time-dependent behavior of negative hydrogen ion extraction from a negative ion source has been studied by particle-in-cell simulation in the collisionless limit.The simulations have shown that,due to the diference in dynamics between electrons and ions,the imbalance of the numbers of charged particles occurs in the source,results in the broadening of plasma sheath and the great increase of plasma potential.The resultant high sheath field and the ambipolar electric field in plasma make the negatively charged particles congregate inside the sheath and move toward the extraction outlet.The emission area of negative ions is much smaller than that of the extraction aperture,which is in sharp contrast to the case of positive ion extraction.     

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。     

Hefei utility negative ions test equipment with RF source: commissioning and first results

In order to study the key technology and physics of RF driven negative ion source for neutral beam injector in China, the Hefei utility negative ions test equipment with RF source was developed at Institute of Plasma Physics, Chinese Academy of Sciences (ASIPP). Its negative ion source can be equipped with single or double RF drivers. There is a plasma expansion chamber with depth of 19 mm and an enhanced filter field. A three electrodes negative ion accelerator was employed to extract and accelerate the negative ions, which are plasma grid, extraction grid and ground grid. And there are several diagnostic tools for the plasma and beam parameters measurement. The characteristics of plasma generation, negative ion production and extraction were studied on the test equipment. The negative ion beam was extracted from the RF driven negative ion source for the first time. The detailed structure and main results are presented in this article.     

Millimeter-Scale PIG Source for Miniature Mass Spectrometers

A new millimeter-scale penning ion generator (PIG) ion source has been developed for miniature mass spectrometers. The cathode is a 40?mm diameter?×?2?mm long stainless steel cylinder with a hole of 4?mm, the anode with a hole of 12.6?mm and a length of 6.4?mm is made in stainless steel, and the ion emission hole size on the anticathode is 5?mm. Several microamperes of H⁺ ions can be extracted with less than 10?W discharge power consumption. The PIG ion source is shown to have advantages of long lifetime under high-pressure operation and low power consumption. The ion source is being designed and investigated for use in miniature mass spectrometer; however this ion source is thoroughly described so that it can be easily implemented by other researchers for other applications.     

中子管内潘宁离子源的建模与控制

由于中子管内离子源电流滞后于储存器电流，导致离子源电流的调节速度和稳定性不够高，进而影响中子产额的稳定性。本文在分析大量实验数据的基础上，建立了中子管离子源的数学模型，设计出相应的PID控制算法。经测试表明：所构建的离子源模型与实际离子源工作情况符合较好，改进的控制算法能减少稳定离子源电流所需时间，提高中子产额的稳定性。     

间热式大面积六硼化镧中空阴极

介绍了适用于强流离子源的间热式大面积六硼化镧中空阴极。在１５ｃｍ双潘宁离子湖泊 上放电特性研究表明，该阴极性能良好，能可靠工作，使用过程中多次暴露于大气中，发射性能并未变坏，加热功率为１．４５ｋＷ，ＬａＢ６发射电流密度为２０Ａ／ｃｍ＾２，放电电流４００Ａ，脉冲宽度３０ｍｓ，放电波形重复性很好。使用１００ｈ后，发射体尺寸无明显变化。     

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.