Beam Dynamics Study for CYCIAE-100

To meet the need of the installation of the RF cavities, the hill gap is increased from 5 cm to 6 cm in the central region, and from 4 cm to -5 cm at the outer region so as to provide space for the RF liner. In the meantime, the space between the hills in the central region brings an easier engineering design of the centering coils. However, for such kind of compact machine, the fringe field at both sides of the sector magnet is quite important for the vertical focusing. So, the basic geometry is studied again and the field distribution is produced for beam dynamics study.     

50 MeV负氢回旋加速器主磁铁设计研究

本文介绍了50 MeV负氢回旋加速器（CYCIAE-50）的总体设计考虑和主磁铁系统的优化设计过程及结果。确定了CYCIAE-50主磁铁的主要尺寸参数,建模计算出满足等时性的主磁铁中心平面磁场。通过调整参数,优化了主磁铁的峰值磁场、局部饱和等,以控制建造及运行成本。优化了磁极张角与磁气隙高度等参数,使负氢离子满足轴向和径向的聚焦要求,避免穿越有害共振。最后对主磁铁的结构进行形变校核,并估计了形变对束流动力学的影响。设计结果表明,CYCIAE-50的主磁铁设计符合要求,可为后续其他系统的设计和建造提供重要参考。     

Wobbling Magnet Design for the Beam Line of CYCIAE-100

In most cases, the extracted beam from cyclotrons is in Gaussian distribution, while in many applications uniformly distributed beam is needed. On account of this, the wobbling magnet is designed to satisfy the need. The wobbling magnet can form a uniform rolling magnet field perpendicular to the beam transfer direction, which enables the beam through the wobbling magnet to turn with it. As a result, the uniformity of the beam will be improved. Figure 1 suggests the course of turning.     

高能大功率电子辐照加速器270°偏转光路设计

为实现高能大功率电子辐照加速器的一机多用目的,需研制270°偏转光路支线。本文采用Trace3D程序对270°偏转光路进行了设计与模拟计算,设计了双135°偏转磁铁和整体270°偏转磁铁。对双135°和整体270°两种偏转磁铁元件进行二维和三维电磁场设计与模拟计算,计算结果表明,整体270°偏转磁铁的场分布与光路设计中所要求的物理参数差距较大。由于整体270°偏转磁铁的场分布调整较困难,使工程实施中的束流调试难度较大,因此采用双135°偏转磁铁的光路方案。     

SFC引出磁通道

在原有的ＨＩＲＦＬＳＦＣ引出系统基础上，设计了两个无线圈磁通道。一个通道将ＳＦＣ边缘场改变成正梯度的线性分布场，使引出束流在径向聚焦；另一个通道屏蔽一部分边缘场，使引出束向大半径方向偏转；此外，还设计了１２０°对称的假磁通道，以平衡磁通道给ＳＦＣ带来的一次谐波扰动场。实际的测磁结果表明，磁通道达到了设计的理论要求。此设计完善了ＳＦＣ束流引出系统。     

100 MeV紧凑型回旋加速器主磁铁的三维磁场有限元分析技术

100 MeV紧凑型回旋加速器主磁铁的几何结构十分复杂,但为了形成加速器束流动力学所要求的磁场分布,本文对初步设计的磁铁进行必要的简化。综合采用各种适当的三维有限元网格剖分技术,对该磁铁的磁场进行数值分析,计算精度满足加速器物理设计的要求。     

Magnet lattice design of the SSRF electron-beam transfer lines

Under three-dimensional plane geometrical constraints （ X, Y, θ ）, with two asymmetric achromatic sections, the combined three-section structural FODO-like magnet lattice design is adopted and finely optimized in the SSRF electron-beam transfer lines. The magnet lattice has high flexibility and robustness, and the Courant-Snyder parameters can be easily adjusted within a wide range to meet the requirements of transmission and injection for different operation modes of the linear accelerator, booster synchrotron, and storage ring. In this article, the main parameters of the linear optics design of the SSRF electron-beam transfer lines are described, involving the physical design criteria, the total geometrical layout, the magnet lattice, and the beam Courant-Snyder parameters matching. The studies of the variant beam dynamic simulation program calculations show that the design purpose of the efficient beam transmission and injection will be basically achieved.     

Numerical Simulation of Main Magnet Electromagnetic Force and Deformation for CYCIAE-100 Project

The achievement of magnetic field plays a crucial part in the design of CYCIAE-100 cyclotron, which is assumed to satisfy various beam dynamics requirements. In the compact cyclotron, magnet deformation caused by gravity, electromagnetic force and atmospheric pressure, impacts the distribution of the field on the middle plane and the space nearby. If the deformation caused by gravity and electromagnetic force is small enough, the field change can be compensated in the field mapping and shimming phase. Otherwise,     

Panofsky magnet for the beam extraction from the synchrotron using a fast Q-magnet and RF-knockout

The fast control of the beam spill extracted from a synchrotron is a key function for the spot scanning irradiation in cancer therapy application. The authors propose an extraction method which uses the quadruple field of fast response, as well as the RF-knockout. A Panofsky magnet was developed as a quadruple magnet, with a frequency response of around 10 kHz. The Panofsky magnet has a rectangular beam aperture and plate coils attached to the pole face. A model magnet has been manufactured with ferrite, and static and dynamic magnetic fields were measured. From the measurement we observed that the effects of eddy current in the plate coils were large and the uniformity of the magnetic field gradient in the beam aperture was worse than ±5% with a plate thickness of 0.02 cm and a frequency of current of 10 kHz. For the future, in a detailed design the eddy current effects have to be taken into account.     

合肥光源超导扭摆磁铁模式下线性光学参数补偿

合肥光源是1台专用真空紫外光源，为拓展同步辐射用户可用光范围，在储存环上安装了1台6T的超导扭摆磁铁。超导扭摆磁铁给储存环光学参数带来很大扰动，造成工作点漂移和β函数畸变。最初，在补偿工作点漂移后，成功地存储了束流并产生了硬X射线，但该运行模式下束流寿命短，严重影响其它实验线站的实验工作。在合肥光源二期工程中，重新进行了超导扭摆磁铁补偿计算，在不改变目前储存环磁铁和电源的基础上，同时补偿工作点漂移和β函数畸变，大幅度地改善了束流寿命。     

中国散裂中子源快周期同步加速器磁铁电源系统的研究

目前正在进行可行性研究的中国散裂中子源的主体结构是1台强流质子同步加速器。该加速器的一期目标为注入能量70MeV、引出能量1.6GeV、束流功率100kW、循环工作频率25Hz。文章阐述系统总体结构的设计原则以及二极磁铁（B）和四极磁铁（Q）磁场的跟踪误差要求。     

EAST中性束注入器稳态偏转磁铁的参数设计与估算研究

中性束注入器偏转磁铁是剥离束流中剩余离子的关键设备,它与剩余离子吞食器等内部部件构成了中性束注入器的束偏转系统。束偏转系统的性能对中性束注入器束流的品质及其束传输效率发挥着重要作用。本文根据EAST(Experimental Advanced Superconducting Tokamak,EAST)中性束注入器对束偏转系统的要求,对其偏转磁铁各性能参数进行了估算。为中性束注入器设计了一台用以剩余离子180°偏转的偏转磁铁。该偏转磁铁采用H型二极电磁铁结构;其磁极端面设计为138cm×47cm的圆角矩形结构;其线圈设计为每侧2饼,每饼2层,每层8根的串联结构,导线选用外方内圆空心铜导体,以满足偏转磁铁稳态运行的需要。该设计的偏转磁铁在370 A励磁电流条件下,可提供80keV氘离子束偏转所需的磁场。实验测试结果显示:500 A励磁电流稳态运行条件下,偏转磁铁线圈冷却水温升约21.5℃,该设计结构的偏转磁铁满足EAST中性束注入器满参数稳态运行和未来运行参数逐步提高的需要。     

螺线管透镜聚焦特性

螺线管磁场透镜不可避免地具有球差,因此引起束流发射度增加。该文力图以多种方法改进磁场特性减少球差,计算表明增加磁场极间距离或将磁极头倒角都可以显著地减小球差系数。同时根据螺线管磁场沿轴磁场分布计算透镜的等效参数,它的大小仅与磁路形状有关,与磁场强度无关。     

Study and Practice of Shimming Method to First Harmonic in Compact Cyclotron

Because of the intrinsic asymmetry of the magnet, imperfection of the machining and assembly of the magnet, there is imperfection distribution of field in the median plane of compact cyclotron, and this kind of imperfection will include the various harmonics by Fourier analysis. Due to the existence of the first harmonic field, the envelop of particle will be distorted and oscillated, and meanwhile it will bring the offset of the center of beam trajectory.     

脉冲强磁体专用设计软件开发

在设计脉冲强磁体时,需综合考虑材料的电性能、热性能和机械性能,优化磁体结构,使其达到最佳。本工作开发的脉冲强磁体专用设计软件,不仅能准确计算放电过程、温度和应力分布,还能使用优化技术,寻找最佳磁体结构,提高磁体设计水平和效率。实验结果表明,软件分析结果与实验结果吻合。     

脉冲磁体中电磁与温度场耦合的有限元分析

脉冲强磁体处于复杂的电磁、热、应力等多物理场共同作用下,设计中考虑的因素众多,物理关系复杂,分析过程繁琐。借助大型有限元软件分析工具ANSYS建立了70T脉冲强磁体中电磁、温度场耦合分析模型,实现了磁场与温度场的计算,并通过有限元方法实现了脉冲磁体性能的优化。实验结果表明,磁体样机达到70T磁场水平。     

100MeV回旋加速器中心区结构设计

中国原子能科学研究院建成了100 MeV紧凑型强流质子回旋加速器,其引出能量为75~100 MeV,流强为200μA。安装在回旋加速器狭小磁极气隙的中心区与螺旋静电偏转板是关键部件,其结构设计涉及磁场、高频电场、高压静电场、真空、传热等方面。本文介绍了中心区与螺旋静电偏转板的结构设计及使用情况。在设计过程中,采取加大绝缘距离、优化高频连接结构、增加杂散束流阻拦装置等措施,解决了中心区与螺旋静电偏转板在强流注入时可靠工作的问题。本文对螺旋偏转板进行了传热分析,得出了该螺旋偏转板在强流束注入时的温度分布。设计的中心区和螺旋偏转板已安装在加速器上,20μA/100 MeV的引出束流通过了12h稳定性测试,在加速器测试过程中,中心区工作稳定可靠。     

HIRFL电荷剥离器后切束线物理设计

介绍了ＨＩＲＦＬ切束线的束流动力学设计思想。在此设计中，ＨＩＲＦＬ剥离器后被废弃的多余电荷态束流被一特殊的切割磁铁从主束运线上切割出来，经过一定的动力学制备，有效地传送到一个小实验区，为同时使用ＨＩＲＦＬ的ＳＳＣ中能束流和ＳＦＣ低能束流进行两种物理实验提供了可能性。此设计为切束线工程建设提供了确切的理论依据。     

Analysis of the measurement field of the optical klystron

The measured fields of the optical klystron in NSRL (National Sychrotron Radiation Laboratory)are, given, incluing the distribution on the axis,and the integrated filed distribution.the harmonic magnet fild and the spectra of the spontaneous emission are analyzed,and the multiple fild is presented by fitting the diagram.The influence of the integrated fild on the colse orbit of the beam and on the operation parameters of the storage ring ,and the compensation in the oexperiment are also discussed.     

Numerical and experimental analysis of AC loss for CFETR CS model coil

The central solenoid (CS) is an important com ponent of China Fusion Engineering Test Reactor,for producing,forming and stabilizing plasma in the superconducting tokamak.It is a complicated work to design and manufacture the large superconducting CS magnet,so it is meaningful to design a central solenoid model coil (CSMC) and analyze its electromagnetic properties in advance.In this paper,the structure,design parameters and magnetic field distribution of the CS model coil are dis cussed.The peak power of radial and axial turn conductors and time bucket loss are analyzed by using piecewise-linear method.The CSMC AC loss with different Nb3Sn CICCs and AC loss of ITER CS coil are compared.The special electrometric method to measure AC loss of the CS model coil for fu ture reference is presented.