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120 MeV电子直线加速器对于束流发射度有较高的要求,传统的光学准直难以满足需求。本文研究采用基于在线束流准直方法(Beam Based Alignment,BBA)以实现精度更高的准直,获得更好的束流性能。根据加速器结构配置情况,使用消色散校正法(Dispersion-free Steering Algorithm,DFS),对加速器束流匹配传输段在不同束流抖动情况下进行模拟计算。计算结果表明,DFS算法对于120 MeV电子直线加速器装置的束流准直应用效果良好。 相似文献
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用三梯度法测量束流发射度的研究 总被引:1,自引:0,他引:1
准确测量发射度对加速器束流的调制和性能的评估极端重要,本文介绍在HIRFL(兰州重离子加速器)现有设备基础上,利用三梯度法测量束流发射度的系统,讨论了测量原理和方法,以及测量中要注意的问题.并对数据的计算处理做了详述。专门设计了一套软件系统,以实现束流发射度、束流剖面等束流参数的实时测量。该系统具有可靠性好、测量直观、测量较准确等优点。 相似文献
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随着核物理实验、原子物理、表面物理实验的进一步发展以及加速器技术在各领域的广泛应用,对离子源产生的束流品质的要求也越来越高。束流发射度是束流品质的一个重要指标,因此,对离子源束流发射度的测量和研究,对离子源技术本身、加速器研究以及相关应用技术都具有重要意义及参考价值。 相似文献
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螺线管透镜具有轴对称性、结构尺寸小等优点,在束流传输系统中得到了广泛应用,然而螺线管透镜磁场的非线性部分(像差)会导致束流发射度增长,降低束流的传输效率。本文采用TRACK程序模拟,研究了螺线管透镜像差与束流发射度增长的关系,发现束流发射度的增长与磁透镜的磁感应强度有关,同时优化螺线管透镜的磁场均匀性有效抑制了束流发射度增长。此外,基于一种磁场均匀度较高的螺线管透镜研究了离子源引出系统与加速管的束流匹配过程,结果表明相比汇聚入射束和准平行入射束,发散入射束通过加速管后的束流包络较小,束流发散相对较缓慢。 相似文献
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中心区的设计中束流发射度的匹配非常重要,因束流匹配将直接影响其在机器内加速过程中的损失情况及引出束流的品质。加速器中心区的聚焦与相位相关,即依赖于相位。因此,要求束流在加速器内的轴向包络最小化的初始发射度是相位的函数。计算中心区的接收度为轴向注入线和偏转板的设计提供匹配条件。对CYCIAE-100回旋加速器的中心区进行轴向接收度的计算研究,分别采用数值和半解析的方法,并对这三种方法进行比较。 相似文献
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为调试100 MeV回旋加速器高功率束流及放射性同位素研制,设计了一条高功率质子束流线及可插拔式高功率束流调试靶。研究了100 MeV回旋加速器引出区色散效应及剥离膜的散射效应,从而优化了光学模拟的初始参数,使得模拟结果更加精确。高功率束流调试靶设计为可插拔式以代替常用固定式调试靶,该靶插入束流管道中时可进行高功率质子束流调试,在拔出时,质子束流可直接轰击束流线终端的靶站以生产放射性同位素。优化了高功率束流调试靶的水冷结构,确保调试靶可承受500 μA以上的质子束流。经调试,该束流线可传输最高流强520 μA的质子束流。 相似文献
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HU Chundong 《等离子体科学和技术》2013,15(3):201-203
Neutral beam injection (NBI) is recognized as one of the most e®ective means for plasma heating. A 100 s long pulse neutral beam with 30 keV beam energy, 10 A beam current and a 100 s long pulse modulating neutral beam with 50 keV beam energy, 16 A beam current were achieved in the EAST neutral beam injector on the test-stand. The preliminary results suggest that EAST-NBI system initially possess the ability of long pulse beam extraction. 相似文献
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用小型化的质量分析系统进行脉冲离子束流实验研究时,从真空弧离子源中引出的束流脉冲幅度大、能量低,由于空间电荷效应使脉冲束流发散度很大,使得离子束流成分分析的不确定度增大。为克服在有限的空间范围内脉冲离子束流聚焦的困难,研制了一种新的双限束光阑三膜片透镜离子束流聚焦装置。双限束光阑着重减少束流发射度,三膜片透镜则适合小尺度空间的脉冲束流聚焦。计算机模拟的结果符合这种大脉冲离子束流聚焦的设计思想。磁质谱仪应用该聚焦装置后,发散到质量分析器分析盒上的脉冲离子束流幅值从未加聚焦前的115 mA减少至0.06 mA,脉冲离子束流质量分析的不确定度降低。 相似文献
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The transport characteristics of a space chargedominated multi-species deuterium beam consisting of D_1~+,D_2~+, and D_3~+ particles in an electrostatic low-energy beam line are studied. First, the envelope equations of the primary D_1~+ beam are derived considering the space charge effects caused by all particles. Second, the evolution of the envelope of the multi-species deuterium beam is simulated using the PIC code TRACK, with the results showing a significant effect of the unwanted beam on the transport of the primary beam. Finally, different injected beam parameters are used to study beam matching, and a new beam extraction system for the existing duoplasmatron source is designed to obtain the ideal injected beam parameters that allow a D_1~+ beam of up to 50 m A to pass unobstructed through the electrostatic low-energy beam transport line in the presence of an unwanted(D_2~+, D_3~+)beam of 20 m A; at the same time, distortions of the beam emittance and particle distributions are observed. 相似文献
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This paper presents the Enhanced Raman scattering of a elliptical laser beam in a collisionless plasma. The transverse intensity
gradient of a pump beam generates a Ponderomotive force, which modifies the background plasma density profile in a direction
transverse to pump beam axis. This modification in density effects the incident laser beam, plasma wave and back-scattered
beam. Non-linear differential equations for the beam width parameters of pump laser beam, plasma wave and back-scattered beam
are set up and solved numerically. The interplay between the self-focusing of the main beam and SRS has been studied in detail.
The analysis clearly shows a coupling between the main beam and the plasma wave, therefore an increase in the self-focusing
of the pump beam at lower intensities increases the self-focusing of the plasma wave which inturn leads to an increase in
the back-reflectivity of the scattered wave. Further, it is also predicted that strong self-focusing of the pump beam at higher
plasma density leads to strong self-focusing of the plasma wave and results in an increase in SRS reflectivity. 相似文献
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合肥光源由800MeV电子储存环、200MeV直线加速器和束流输运线组成。束流输运线线性光学参数是影响束流传输效率和储存环注入效率的关键因素。在分析合肥光源现束流输运线性能基础上,重新优化设计输运线聚焦结构。新设计在改善输运线与储存环之间Twiss参数和色散函数匹配基础上,更好地控制传输过程中束流包络,并减轻了开关磁铁幅度抖动对传输束流末态位置的影响。通过优化光学参数设计,束流传输效率将明显改善,同时参数匹配将有利于提高储存环注入效率。并且,新设计中的主磁铁磁场强度较低,输运线具备传输800MeV束流的能力。 相似文献
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In gyrotron, there is the chance of generation and excitation of unwanted RF modes (parasite oscillations). These modes may
interact with electron beam and consequently degrade the beam quality. This paper presents the improved design of the beam
tunnel to reduce the parasite oscillations and the effect of beam tunnel geometry on the electron beam parameters. The design
optimization of the beam tunnel has been done with the help of 3-D simulation software CST-Microwave Studio and the effect
of beam tunnel geometry on the electron beam parameters has been analyzed by EGUN code. 相似文献
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在不透明靶的前角反冲测量中,对束流与靶表面的夹角精度要求较高。当这一夹为角15°±1°时观引起有效靶厚误差为6—7%。我们实验室的散射室,原设计没有考虑这一角度的测量。为测这一角度,对散射室做了一点改进。方法简单易行。在位于散射室中心的靶杆(图1)上端,装一个平面反射镜的镜架(图1a)。镜架要能绕靶杆转动轴相对靶杆转动,镜架转动中心必须与靶杆转动轴重合亦即使靶杆转动轴位于镜架转动中心面上。 相似文献