10MeV电子直线加速器磁聚焦系统研究进展

磁聚焦系统是电子直线加速器的重要组成部分,10 MeV电子直线加速器的磁场聚焦系统主要依据加速管轴线上的磁场分布进行工程设计。 1 设计要求 依据束流动力学理论计算的结果(图1)进行设计。 图1 理论磁场曲线图 2 聚焦元件布局 根据理论磁场曲线,在加速管上布置6个聚焦线圈     

10MeV大功率辐照加速器研究进展

10 MeV辐照加速器输出电子束能量10 MeV,平均束流功率达20 kW。由于高流强、大功率,对加速器的总体和一些关键部件如加速管、速调管、调制器、电子枪等提出更高的要求。经充分的预研、设计与计算,完成了加速器总体结构与各分系统的工程设计。总体采用立式机架,束流由上往下传输     

海关集装箱检测用电子直线加速器聚焦线圈磁场设计与测试

介绍了在电子直线加速器粒子动力学基础上进行聚焦线圈轴向磁场的设计；利用ＬＩＮＥ－ＡＣＣ／ＰＣ程序模拟计算，给出了不同初始发射度情况下满足束流包络要求的各种聚焦磁场数据。对已经加工好的聚焦系统进行了磁场分布测量，并将实际磁场与理论计算进行了比较。上述工作为确定聚焦线圈的设计方案和加速器的出束实验提供了可靠、丰富的数据。     

海关集装箱检测用电子直线加速器聚集线圈磁场设计与测试

介绍了在电子直线加速器粒子动力学基础上进行聚集线圈轴向磁场的设计；利用ＬＩＮＥ－ＡＣＣ／ＰＣ程序模拟计算，给出了不同初始发射度情况下满足束流包络要求的各种聚焦磁场数据。对已经加工好的聚焦系统进行了磁场分布测量，并将实际磁场与理论计算进行了比较。上述工作为确定聚焦线圈的设计方案和加速器的出束实验提供了可靠、丰富的数据。     

10 MeV大功率辐照加速器研制进展

2004年,10MeV大功率辐照加速器完成了加速器主体及各分系统的安装、接线。分别实验调试了高压调制器、微波系统、控制系统、水冷系统、真空系统、束流聚焦与扫描系统等加速器各分系统。在加速器各分系统的联合调试实验中,较好地解决了一些关键的技术问题。如真空密封、大功率散     

CYCIAE-100 MeV回旋加速器机械工程介绍

CYCIAE-100MeV回旋加速器非标机械结构主要包括离子源、轴向注入、中心区、高频腔体、频率自动微调、高频功率馈入、剥离靶引出、磁场调谐系统、对中线圈、径向束流探针、真空系统、相位探测系统、磁场测量系统、主线圈、束流诊断系统、束流调试靶、质子管道及传输元件、举升系统、运输安装与调节系统等。初步机械工程设计工作涉及到回旋加速器研制的各个方面,包括各系统为实现其功能所进行的结构设计、工艺设计、相关专业调研、加工方法、厂家选择、技术交流、采购、监造、分系统安装、分系统调试、验收、整体安装、整机调试、检修、运…     

基于束流变压器的辐照加速器束流流强测量系统

加速器产生的电子束广泛应用于食品加工以及医疗卫生行业,为满足辐照加工中对剂量控制的要求,需要对加速器输出流强进行实时测量。基于10 MeV加速器脉冲束流流强的大小,提出一种束流变压器的测量方案,并根据束流变压器的输出特性设计了一套测量电路,包含阻抗匹配、放大电路、采样保持电路、压频转换电路及可编程逻辑控制器(PLC)处理电路等模块。在实验室搭建简易模拟束流电路对束流变压器进行定标,定标结果与模拟束流的拟合曲线线性度好,实际增益与理论分析基本符合。系统在10 MeV/20 kW加速器上进行了实验验证,测量输出结果稳定,可靠性高,可为辐照加工的工艺研究提供参考。     

回旋加速器中心区实验装置剥离引出计算分析

改进了30 MeV回旋加速器剥离引出程序CYCTRS,计算了10 MeV回旋加速器不同能量束流引出剥离点的位置,着重计算分析了10 MeV能量点的束流剥离引出的光学特性,为设计加工束流引出系统提供了重要的参数依据。 10 MeV回旋加速器加速H-离子,采用剥离引出。该加速器将主要用于强流加速     

13 100MeV回旋加速器剥离引出系统研制

100MeV回旋加速器加速H^-离子，要求引出束流能量为75～100MeV、束流强度为200μA的质子束流，因此决定采用剥离引出。本工作依据100MeV主磁场数据和平衡轨道数据，通过理论研究，计算100MeV回旋加速器不同能量束流引出剥离点的位置；着重计算分析70～100MeV能量的束流剥离引出的光学特性；通过理论计算确定剥离膜各项参数；完成剥离靶及其伺服驱动装置的设计；对真空系统、控制系统等相关专业提出明确的工艺流程和技术要求。最终确定100MeV强流质子回旋加速器双向引出系统初步设计。     

10 CYCIAE-100 MeV回旋加速器机械工程介绍

CYCIAE-100MeV回旋加速器非标机械结构主要包括离子源、轴向注入、中心区、高频腔体、频率自动微调、高频功率馈入、剥离靶引出、磁场调谐系统、对中线圈、径向束流探针、真空系统、相位探测系统、磁场测量系统、主线圈、束流诊断系统、束流调试靶、质子管道及传输元件、举升系统、运输安装与调节系统等。     

重离子加速器磁铁电源控制系统研制

重离子加速器通过一定周期的磁场对带电粒子进行约束,磁铁电源是产生所需磁场的关键部件,因此,要求磁铁电源控制系统具备高效性、稳定性、精确性。磁铁电源需按加速器运行周期进行响应运行。重离子加速器磁铁电源的时序必须严格按重离子加速器控制系统的控制时序进行控制。本工作研制了重离子加速器磁铁电源控制系统,通过磁铁电源控制器与同步时钟系统的通信进行控制时序的运行;通过与中央数据库的数据通信获取磁铁电源控制器所需的全部数据(如同步事例数据、波形数据等)。同步时钟信号一旦触发,磁铁电源控制器进行相应的数据获取并进行插值运算输出至磁铁电源进行控制。重离子加速器磁铁电源控制系统同步精度为1μs,实验平台测试控制器平台纹波精度为100ppm,能满足重离子加速器实验运行的要求。     

电子束真实发射度测量原理

描述了一个新的发射度测量方法.它包括有磁扫描系统,厚窄缝,荧光屏以及CCD图像处理系统.这个方法能够测量出电子束的真实发射度图形.文章设计了磁扫描系统,估计了束流通过磁扫描系统引起的发射度增长,还讨论了为阻挡高能电子穿透,窄缝必须选择的厚度.电子束发射度的测量对于自由电子激光以及其它对束流品质要求较高的加速器装置都是很重要的.     

A fast switching electrostatic deflector system for actinide isotopic ratio measurements

We have implemented a fast switching electrostatic system on the actinides beamline on the ANTARES accelerator at ANSTO, to improve the precision of analyses by accelerator mass spectrometry. This high-energy bouncing system is based on a pair of deflector plates, deflecting in the orbit plane, set at the entrance and exit of the analysing magnet. The design of deflector plates is unique, and it was modelled by SIMION in order to minimize field inhomogenity and fringe field effects. The pair of deflector plates are supplied by a high-voltage amplifier driven by an EPICS-enabled control unit, with two 4 W power supplies providing up to ±10 kV modulation. The high-energy bouncing system is synchronized with the existing low-energy bouncing system. To measure the isotopic ratio with the new system, the magnetic fields of the injector and analysing magnets are set to transmit selected isotopes along the beam line with zero voltage applied. The other isotopes of interest are transmitted by keeping the magnetic fields constant and modulating the voltages on the injector magnet chamber and on the high-energy deflector plates.     

A new magnetic scanning system for proton microprobe

Design of a new beam scanning system with ferrite-cored magnetic coils is described. Results of testing of the system are presented. Deflecting magnetic field produced by the scanning system shows high degree of uniformity. The fringing fields are decreased sharply along the magnet axis.     

无偏估计方法提高电子束的扫描均匀度

电子束扫描均匀是辐照电子加速器的重要指标之一，采用无偏估计方法对电子束的扫描均匀度作校正是一种有效的方法。在考虑到加速器束流强度稳定性的基础上，90%扫描宽度的扫描均匀度可达到2.3%（规一化RMS）。     

重离子扫描磁铁系统的研制

文章给出了重离子扫描磁铁物理设计的实用公式，指出这种磁铁系统工艺设计中应考虑的事项，并给出扫描磁铁系统的研制和实测结果。该磁铁最大可产生０．５０Ｔ的交流磁场，重复频率为５０Ｈｚ，通过３ｍ的漂移管道可将１６５ＭｅＶ＾７９Ｂｒ＾１４＾＋的离子扫宽０．４ｍ，满足了在ＨＩ－１３串列加速器上辐照ＰＥＴ一类膜材的要求，为生产核微孔膜高级滤材提供基本保证。     

扫描磁铁的研制

根据3MeV/40mA高频高压加速器总体设计要求,对扫描磁铁的结构进行了改进,在芯管壁上安置了热敏电阻,增加了风冷装置.由钛窗挡板的束流性能测定结果表明,扫描磁铁的性能已达到设计指标,扫描频率为50-200周,扫描均匀度好于±7%.     

First direct-write lithography results on the Guelph high resolution proton microprobe

The recently completed high-resolution proton microprobe at the University of Guelph is Canada’s first one-micron nuclear microprobe, which represents the country’s state-of-the-art technology for various nuclear microprobe applications, e.g. direct-write microlithography. Its probe-forming system is comprised of a triplet Oxford Micro beams magnetic quadrupole lenses, along with high-precision objective slits. High energy protons coming off a 3 MV particle accelerator can achieve a nominal resolution of one micro and a beam current of several hundred of picoamperes when arriving at the target. This proton probe is ideal for the use of direct-write lithography with the incorporation of a magnetic scanning system and motorized sample stage.Preliminary lithography results have been obtained using spin-coated PMMA photoresist as specimen. The beam spot size, beam range and straggling inside the substrate and the exposure conditions are investigated by using scanning electron microscopy. This facility is the first in Canada to perform focused direct-write ion beam lithography, which is ideal for modification and machining of polymer and semiconductor materials for biological, microfluidic and ultimate lab-on-chip applications.     

Preliminary design of KTX magnet system

KTX is a reversed field pinch magnetic confinement device of which the magnet system is designed in ASIPP and USTC. The main parameter of KTX is between RFX and MST. Its magnet system includes the toroidal field (TF) winding and poloidal field (PF) winding (ohmic heating winding and equilibrium field winding), which are less complex than tokamak device due to the fact that a tokamak requires a superconducting system to perform quasi-steady state operation and achieve Q > 10. However, the most important part of the magnet system design lies in how to keep the TF magnetic field ripple, as well as any kinds of stray field, to a minimum value. The main design activities of the KTX magnet system are presented as detailed as possible in this paper, and the main activities which have already been completed include magnet coils position and winding, insulation design, plasma modeling prediction, thermal analysis, magnetic field calculations were analyzed and so on. The magnet system design is one of the major activities for KTX device design, which is effective guarantee for the future R&D and manufacture. Besides, the detailed design activities should be continuously optimized and changed based on the results from future R&D and relevant tests.     

Tunable biasing magnetic field design of ferrite tuner for ICRF heating system in EAST

Ion cyclotron range of frequency(ICRF) heating has been used in tokamaks as one of the most successful auxiliary heating tools and has been adopted in the EAST. However, the antenna load will fluctuate with the change of plasma parameters in the ICRF heating process. To ensure the steady operation of the ICRF heating system in the EAST, fast ferrite tuner(FFT) has been carried out to achieve real-time impedance matching. For the requirements of the FFT impedance matching system, the magnet system of the ferrite tuner(FT) was designed by numerical simulations and experimental analysis, where the biasing magnetic circuit and alternating magnetic circuit were the key researched parts of the ferrite magnet. The integral design goal of the FT magnetic circuit is that DC bias magnetic field is 2000 Gs and alternating magnetic field is±400 Gs. In the FTT, E-type magnetic circuit was adopted. Ferrite material is Nd Fe B with a thickness of 30 mm by setting the working point of Nd Fe B, and the ampere turn of excitation coil is 25 through the theoretical calculation and simulation analysis. The coil inductance to generate alternating magnetic field is about 7 m H. Eddy-current effect has been analyzed, while the magnetic field distribution has been measured by a Hall probe in the medium plane of the biasing magnet. Finally, the test results show the good performance of the biasing magnet satisfying the design and operating requirements of the FFT.