共查询到20条相似文献,搜索用时 0 毫秒
1.
A triode extraction system is designed for a dual hollow cathode ion source being developed at the Institute of Heavy Ion Physics, Peking University. Basic parameters of the plasma are selected after examining the operation principle of the ion source, then the triode extraction system is designed and optimized by using software PBGUNS (for Particle Beam GUN Simulations). The physical design of the system is given in this paper. 相似文献
2.
空间推进所用的电子回旋共振离子源(ECRIS)应具有体积小、效率高的特点. 本文研究的ECRIS使用永磁体环产生磁场, 有效减小了体积, 该离子源利用微波在磁场中加热电子, 电子与中性气体发生电离碰撞产生等离子体. 磁场在微波加热电子的过程中起关键作用, 同时影响离子源内等离子体的约束和输运. 通过比较四种磁路结构离子源的离子电流引出特性来研究磁场对10 cm ECRIS性能的影响. 实验发现: 在使用氩气的条件下, 特定结构的离子源可引出160 mA的离子电流, 最高推进剂利用率达60%, 最小放电损耗为120 W·A-1; 所有离子源均存在多个工作状态, 工作状态在微波功率、气体流量、引出电压变化时会发生突变. 离子源发生状态突变时的微波功率、气体流量的大小与离子源内磁体的位置有关. 通过比较不同离子源的引出离子束流、放电损耗、气体利用率、工作稳定性的差异, 归纳了磁场结构对此种ECRIS引出特性的影响规律, 分析了其中的机理. 实验结果表明: 保持输入微波功率、气体流量、引出电压不变时, 增大共振区的范围、减小共振区到栅极的距离, 离子源能引出更大的离子电流; 减小共振区到微波功率入口、气体入口的距离能降低维持离子源高状态所需的最小微波功率和最小气体流量, 提高气体利用率, 但会导致放电损耗增大. 研究结果有助于深化对此类离子源工作过程的认识, 为其设计和性能优化提供参考. 相似文献
3.
The design requirement and principle of the deflection magnet for Magnetron and Penning H- ion source are discussed.It is proved that there exists a maximum emittance for the beam that may be transformed by the magnet into a state with equal Twiss parameters of αr=αy and βr =βy,which is the requisite condition to get a minimum emittance at the entrance of RFQ after transporting by a LEBT with solenoids.For this maximum emittance,the corresponding magnetic field gradient index is 1. 相似文献
4.
The design requirement and principle of the deflection magnet for Magnetron and Penning H- ion source are discussed. It is proved that there exists a maximum emittance for the beam that may be transformed by the magnet into a state with equal Twiss parameters of αr =αy and βr =βy, which is the requisite condition to get a minimum emittance at the entrance of RFQ after transporting by a LEBT with solenoids. For this maximum emittance, the corresponding magnetic field gradient index is 1. 相似文献
5.
6.
A new ion source has been designed and manufactured for the CYCLONE30 accelerator, which has a much advanced performance compared with the original. It is expected that the newly designed ion source extraction system will transport a very large percentage of the beam without deteriorating the beam optics, which is designed to deliver an H- beam at 30 keV. The accelerator assembly consists of three circular aperture electrodes made of copper. The simulation study was focused on finding parameter sets that raise the beam perveance as large as possible and which reduce the beam divergence as low as possible. Ion beams of the highest quality are extracted whenever the half-angular divergence is minimum, for which the perveance current intensity and the extraction gap have optimum values. The triode extraction system is designed and optimized by using CST software (for Particle Beam Simulations). The physical design of the extraction system is given in this paper. From the simulation results, it is concluded that it is possible to achieve this goal by decreasing the thickness of the plasma electrode, shortening the first gap, and adjusting the acceleration electrode voltage. 相似文献
7.
A new ion source has been designed and manufactured for the CYCLONE30 accelerator, which has a much advanced performance compared with the original. It is expected that the newly designed ion source extraction system will transport a very large percentage of the beam without deteriorating the beam optics, which is designed to deliver an H- beam at 30 keV. The accelerator assembly consists of three circular aperture electrodes made of copper. The simulation study was focused on finding parameter sets that raise the beam perveance as large as possible and which reduce the beam divergence as low as possible. Ion beams of the highest quality are extracted whenever the half-angular divergence is minimum, for which the perveance current intensity and the extraction gap have optimum values. The triode extraction system is designed and optimized by using CST software (for Particle Beam Simulations). The physical design of the extraction system is given in this paper. From the simulation results, it is concluded that it is possible to achieve this goal by decreasing the thickness of the plasma electrode, shortening the first gap, and adjusting the acceleration electrode voltage. 相似文献
8.
The permanent magnets of the discharge chamber in a multi-cusp proton source are studied and designed. The three electrode extraction system is adopted and simulated. A method to extract different amounts of current while keeping the beam emittance unchanged is proposed. 相似文献
9.
This work is concerned with ion beam dynamics and compares the emittance to aberration ratios of two-and three-electrode extraction systems. The study is conducted with the aid of Version 7 of SIMION 3D ray-tracing software. The beam dependence on various parameters of the extraction systems is studied and the numerical results lead to qualitative conclusions. 相似文献
10.
The permanent magnets of the discharge chamber in a multi-cusp proton source are studied and designed.The three electrode extraction system is adopted and simulated.A method to extract different amounts of current while keeping the beam emittance unchanged is proposed. 相似文献
11.
Theoretical analysis of a new extraction system for a DUHOCAMIS operating in a high magnetic field 下载免费PDF全文
A new extraction system is designed for a penning ion source DUHOCAMIS(dual hollow cathode ion source for metal ion beams)being installed at the Institute of Heavy Ion Physics,Peking University.We have analyzed theoretically the central particle trajectories in the extraction region for ions having different q/m ratios and then compared our results with the simulation results of CST(Computer Simulation Technology)software.The validity of the system is verified and some analytical formulas are obtained which will be used for the optimization of the extraction system as well as the experimental setup. 相似文献
12.
A new extraction system is designed for a penning ion source DUHOCAMIS (dual hollow cathode ion source for metal ion beams) being installed at the Institute of Heavy Ion Physics,Peking University.We have analyzed theoretically the central particle trajectories in the extraction region for ions having different q/m ratios and then compared our results with the simulation results of CST (Computer Simulation Technology) software.The validity of the system is verified and some analytical formulas are obtained which will be used for the optimization of the extraction system as well as the experimental setup. 相似文献
13.
14.
15.
等离子体源离子注入过程(PSII)中样品温度是一个非常重要的参量。由于注入到样品上的能量很大,导致样品温度很高,所以在实验中获知样品的温度分布有着很重要的意义。本文利用热传导方程建立了半圆形碗状样品内部温度升高模型,研究样品内温度演化过程。以注入离子束流作为能量输入项,热辐射为能量损失项,并考虑了热辐射过程中样品的形状因子的影响。考察了离子注入过程中样品上所施加负偏压的脉冲宽度和频率对样品温度分布的影响。研究结果显示,脉冲频率达到一定值后,样品温度不再随频率增加而升高。 相似文献
16.
微型电子回旋共振(ECR)离子推力器可满足微小航天器空间探测的推进需求. 为此, 本文开展直径20 mm的微型ECR离子源结构优化实验研究. 根据放电室内静磁场和ECR谐振区的分布特点, 研究不同微波耦合输入位置对离子源性能的影响, 结果表明环形天线处在高于ECR谐振强度的强磁场区域时, 微波与等离子体实现无损耦合, 电子共振加热效果显著, 引出离子束流较大. 根据放电室电磁截止特性, 结合微波电场计算, 研究放电容积对离子源性能的影响, 实验表明过长或过短的腔体长度会导致引出离子束流下降甚至等离子体熄灭. 经优化后离子源性能测试表明, 在入射微波功率2.1 W、氩气流量14.9 μg/s下, 可引出离子束流5.4 mA, 气体放电损耗和利用率分别为389 W/A和15%. 相似文献
17.
18.
Mass analyzed highly charged ion beams of energy ranging from a few keV to a few MeV plays an important role in various aspects
of research in modern physics. In this paper a unique low energy ion beam facility (LEIBF) set up at Nuclear Science Centre
(NSC) for providing low and medium energy multiply charged ion beams ranging from a few keV to a few MeV for research in materials
sciences, atomic and molecular physics is described. One of the important features of this facility is the availability of
relatively large currents of multiply charged positive ions from an electron cyclotron resonance (ECR) source placed entirely
on a high voltage platform. All the electronic and vacuum systems related to the ECR source including 10 GHz ultra high frequency
(UHF) transmitter, high voltage power supplies for extractor and Einzel lens are placed on a high voltage platform. All the
equipments are controlled using a personal computer at ground potential through optical fibers for high voltage isolation.
Some of the experimental facilities available are also described. 相似文献
19.
A penning plasma surface H- ion source test stand for the CSNS has just been constructed at the IHEP. In order to achieve a safe and reliable system, nearly all devices of the ion source are designed to have the capability of both local and remote operation function. The control system consists of PLCs and EPICS real-time software tools separately serving device control and monitoring, PLC integration and OPI support. This paper summarizes the hardware and software implementation satisfying the requirements of the ion source control system. 相似文献
20.
Influence of ion species ratio on grid-enhanced plasma source ion implantation 总被引:1,自引:0,他引:1 下载免费PDF全文
Grid-enhanced plasma source ion implantation (GEPSII) is a newly proposed technique to modify the inner-surface properties of a cylindrical bore. In this paper, a two-ion fluid model describing nitrogen molecular ions N_2^+ and atomic ions N^+ is used to investigate the ion sheath dynamics between the grid electrode and the inner surface of a cylindrical bore during the GEPSII process, which is an extension of our previous calculations in which only N_2^+ was considered. Calculations are concentrated on the results of ion dose and impact energy on the target for different ion species ratios in the core plasma. The calculated results show that more atomic ions N^+ in the core plasma can raise the ion impact energy and reduce the ion dose on the target. 相似文献