The China Institute of Atomic Energy (CIAE) is developing a proton cyclotron with an energy of 9.5 MeV and a current of 100 mu A. To evaluate the performance of the cyclotron, the beam dynamics study has been conducted. Static and dynamic orbit analyses combined with phase-space matching were used to assess its beam acceptance and acceleration capability. Particle tracking simulations were employed to calculate characteristics such as radial centering and axial focusing, and the structure was optimized accordingly. The extracted beam parameters were controlled by adjusting the tilt angle of the stripping foil. The phase acceptance of this cyclotron exceeds 60 degrees, and the beam size at the liquid target is 1.35 mm & times; 2.01 mm. The cyclotron has entered the beam commissioning stage, with measured beam currents of 107 mu A at the internal target and 65 & micro;A of extracted beam current at the Faraday cup after stripping.

To address the heavy reliance on imported medical cyclotrons in China，the China Institute of Atomic Energy has independently developed a 10 MeV ultra-compact cyclotron，aiming at achieving localized and low-cost production of medical radioisotopes. The device incorporates key technologies including shallow-valley magnets，an integrated high-frequency and vacuum system，single-pass axial shimming，and an internal Penning ion source. It has a compact footprint of less than 1.4 m3 and a total weight under 7.5 tons，and is designed for high integration and intelligent operation and maintenance. Under working conditions of 10 MeV proton energy with 80 μA beam current，the cyclotron maintained stable operation for 2 h，yielding 18F with an activity of over 3 Ci. This output is sufficient for approximately 15 patient doses，fulfilling the clinical demand. The results demonstrate that this accelerator is reliable，user-friendly，and suitable for in-hospital production of short-lived medical radioisotopes such as 18F and 68Ga.

As the research work about irradiation effect and neutron measurement requires high-energy neutron with the development in the fields of space exploration, medical treatment and high-energy physics investigation, a beamline of quasi-monoenergetic neutron in the range of 30 similar to 50 MeV based on a proton cyclotron with a maximum energy of 50 MeV is under construction and preparation. We studied the design of this quasi-monoenergetic neutron beamline with a focus on target chamber and collimator. Comprehensive comparison on characters of thermodynamic and nuclear physics between lithium and beryllium was conducted, and lithium was chosen as target material by better performance on quasi-monoenergetic neutron peak. Relevant parametric simulations of lithium thickness were carried out in consideration of efficiency and quality of neutron generation which shows the change on height and width of quasi-monoenergetic neutron peak. Energy loss of incident proton caused by titanium film and argon gas was estimated to provide a reference for the mechanical design of target chamber. Evaluation has been done to show the variation of neutron spectra and fluxes at different positions from the target along with collimators of different lengths, and the collimator length was determined to be 2 m in view of flux and ratio of quasi-monoenergetic neutron peak. All work provides a data reference for the building and operation of the quasi-monoenergetic neutron beamline.

A set of nozzle equipment for proton therapy is currently under development at China Institute of Atomic Energy (CIAE). To facilitate the off-line commissioning of the whole equipment, a set of ionization chamber signal generation system, known as the test electronics, was designed. The results showed that the system can simulate the beam position, beam fluence (which exhibits a positive correlation with the dose), and other related analog signals generated by the proton beam when it traverses the ionization chamber. Moreover, the accuracy of the simulated beam position is within ± 0.33 mm, and the accuracy of the simulated beam fluence signal is within ± 1%. The test electronics can output analog signals representing environmental parameters. The test electronics meets the design requirements, which can be used for the commissioning of the nozzle system as well as the treatment control system without the presence of the proton beam.

The compact high-intensity proton cyclotron based on the stripping-extraction method has made great progress and obtained huge applications since the first cyclotron was applicated in 1932 in the world, especially in the field of nuclear medicine. China Institute of Atomic Energy (CIAE) built a 30 MeV compact high-intensity proton cyclotron in the 1990s in China and a series of compact high-intensity proton cyclotrons with energy of 10 MeV, 14 MeV, 100 MeV, 14 MeV/1 mA used in boron neutron capture therapy (BNCT) based on the stripping extraction technology have been developed. The 100 MeV compact high-intensity proton cyclotron (CYCIAE-100) built in 2014 is the largest compact high-intensity proton cyclotron with the higher energy in the world with a maximum current intensity of 520 μA and a beam power of 52 kW. The BNCT cyclotron is also the first high-intensity proton cyclotron with extracted beam reaching the mA level in China. A great progress on the stripping extraction technology used in cyclotrons has been achieved at CIAE during the 60 years development. The codes for stripping extraction studies, such as CYCTR, GOBLIN, STRIP-UBC and COMA, are developed by CIAE too. The study method with the code of GOBLIN for the beam dispersion effect in the stripping extraction cyclotrons was given in detail. The influence of the angle between the stripping foil and the beam to the quality of the extracted beam was analyzed in the paper. The single-turn stripping extraction technology for some special application was used in the stripping extraction cyclotrons. The stripping efficiency and the life of stripping foils were studied in the paper. The beam loss control in the stripping extraction field and stripping probe system were introduced in the end.

在230MeV超导回旋加速器调束的过程中,需要对束流的大小形状和对中情况进行测量分析,束流测量装置可以满足上述要求.本装置利用径向靶和包络靶可以测量半径150mm到850mm范围内的束流,采用了双X型圈密封结构,大大缩短了径向空间,密封性能好.直线驱动装置运动平稳可靠,靶杆带动靶头运动精度高,可为后续的束流测量装置的设计提供参考依据.

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500μA以上的质子束流.经调试,该束流线可传输最高流强520μA的质子束流.

CYCIAE-100, a 100 MeV high current compact cyclotron has been constructed and first beams were extracted in 2014. The machine has 5 beam lines for multi-application purposes. N1, one of the beam lines, is designed for high current beam transportation, for beam dump tests and isotope production. In 2016, a mA proton beam was tested on the internal target. In 2017 and 2018, 200 mu A and 520 mu A proton beams were extracted and transported to the beam dump respectively. In addition to increasing the cw beam power of 52 kW extracted from the machine and transported to the beam dump, this paper will also present the simultaneous dual-beam extraction from CYCIAE-100 and the improvement of the uniformity of the beam spot on the target, which will benefit isotope production.

中国原子能科学研究院研制的100 MeV强流质子回旋加速器是国际上最大的紧凑型强流质子回旋加速器,取得了多项先进束流指标.截至2018年底,该加速器完成了分系统 、整机调试,开展了多项物理实验,已稳定运行2000 h以上.本文将重点介绍100 MeV强流质子回旋加速器的调试过程以及调试中所解决的关键技术问题和调试结果.

In order to monitor and control proton radiography beam line equipment remotely and realize the safety interlock function of various subsystems of the beam line ,a distributed EPICS control system was developed adopting the structure of stand-ard control model .The system achieved the control for switch logic equipment safety chain through PLC .The core control system chose EPICS to set up many IOCs as a controller .The server set up the cross compiling environment under different CPU architectures .The device drivers and development of communication protocols were completed by using StreamDevice for digital power equipment and vacuum instrument equipment .The communication design for IOC and control functions of IOC convection equipment and PLC signals were completed through the establishment of the IOC dynamic database . Using CSS to design OPI , the host computer has access to data transparently in EPICS IOC .The beam line control system has been successfully applied to the physics experiment of CYCIAE-100 cyclotron proton radiography . The stable operation of the control system lays a solid foundation for the launch of the proton radio-graphy experiment and has certain reference value for the development of similar control system .

100 MeV强流质子回旋加速器(CYCIAE-100)加速H-,引出质子束能量为75～100 MeV、最大柬流强度为200 μA.为对束流输运线上的质子束流强度进行无阻挡实时监测,选择了直流流强监测器(DCCT),其在设计上考虑了空间限制、杂散磁场和外部高频干扰信号等因素对探头的影响.探头外采用了三重磁屏蔽设计,磁屏蔽外为1层黄铜的电屏蔽.采用了绝缘垫圈隔断束流输运线的直流导电性,束流输运线管壁通有冷却水以保证探头温度稳定.在绝缘垫圈处增加电容以满足探头对电容值的要求.采用高精度PLC-AI模块对DCCT的输出电压进行了读取.通过模拟束流的实验验证表明,DCCT设计合理可行,测量结果的线性度、误差等指标符合设计要求.

100 MeV强流质子回旋加速器(CYCIAE-100)加速负氢离子,引出系统为电荷交换方式的双向剥离引出系统,剥离靶是引出系统的核心装置.剥离靶系统四维联动定位精度要求高.为满足剥离靶驱动控制系统要求,采用了PLC控制驱动电路,读取位置反馈信号,对运动控制形成负反馈闭环的控制方法,实现了引出系统的各项运动控制要求并达到了设计指标.经调试,该加速器于2014年7月首次成功引出75～100 MeV质子束流,引出效率达99％以上.剥离靶驱动控制系统经加工调试,满足引出系统的各项技术要求,目前已投入运行2 a,可靠性得到了验证.

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.

During the beam commissioning of CYCIAE-100, the beam distributions on radial direction and axial direction are very important parameters for the cyclotron.The radial probe system is the main part of the beam diagnostic system to get these parameters.Three radial probe systems were installed on CYCIAE-100.The beam distributions on radial direction and axial direction were obtained by the radial probe system during the beam accelerating process inside CYCIAE-100.This provides the necessary condition for the improvement of the cyclotron.

In the design of CYCIAE-100 beam diagnostics system, three radial probe targets distribute on three directions above magnetic pole and in the valley on the median plane of cyclotron. These radial probe targets can be used for beam center measurement. By blocking beam on five fingers and one stopping block, the radial probe target can measure the radial and axial distribution of H beam at the same time. During beam commissioning, the radial probe targets can also be used for beam intensity measurement. The changeable target tip design makes it possible to replace the damaged part and optimization of the structure. The mechanical and control part of radial probe target system is finished, assembly and prime test of the whole system will be carried out in September. DESIGN OF RADIAL PPROBE The project of Beijing Radioactivity Ion-beam Facility (BRIF) is being constructed at China Institute of Atomic Energy (CIAE). As a major part of the BRIF project, a 100MeV compact cyclotron (CYCIAE-100) will provide proton beam with an intensity of 200μA 500μA [1]. CYCIAE-100 is a compact isochronous cyclotron. The radius of magnetic pole is 2000 mm, yoke is 3080 mm, air gap between 46-60 mm. Large radius with small axial space plus high requirement of isochronous magnetic field, all these factors lead to the following design of radial probe target: 4580 mm long, placed on the median plane of CYCIAE-100 cyclotron, above the surface of magnetic pole, bellows with compression ratio as high as 0.234 is chosen for vacuum seal. The moving range of radial probe target is 2020 mm to assure the radial probe measurement range near the centre of CYCIAE-100 [2]. When not measuring, radial probe target is blocked off from main vacuum chamber by a gate valve. The position of three radial probe targets on CYCIAE-100 is shown in Fig. 1. Figure 1: Radial probe targets on CYCIAE-100. For the purpose of beam center measurement, three radial probe targets will be installed on three directions above magnetic pole and in the valley on the median plane of CYCIAE-100 cyclotron. Meanwhile, at low energy, radial probe target with water cooling can get real time beam intensity which is important parameter for prime beam commissioning. The main functions of radial probe target are as follows: Get Beam Distribution on Axial and Radial Directions at the Same Time The radial probe target tip, making up by five fingers and one stopping block in front, get the beam distribution on axial and radial directions by blocking the beam. Radial probe target tip is made by copper. The five fingers’ positions are decided according to the calculated axial beam distribution. The five cuboid fingers with 0.5mm cuneate tip outside the stopping block can satisfy the radial resolution requirement. The five fingers are symmetrical to the median plane of CYCIAE-100, as shown in Table 1. Table 1: The Size of Five Fingers Finger No. Position Size

This paper looks specifically at how to develop light weight methods of evaluating pedagogically motivated software. Whilst we value traditional usability testing methods this paper will look at how Heuristic Evaluation can be used as both a driving force of Software Engineering Iterative Refinement and end of project Evaluation. We present three case studies in the area of Pedagogical Software and show how we have used this technique in a variety of ways. The paper presents results and reflections on what we have learned. We conclude with a discussion on how this technique might inform on the latest developments on delivery of distance learning.

介绍了紧凑型回旋加速器CYCIAE-100的特点及设计过程中重点考虑的一些物理问题,如紧凑型直边扇磁铁结构的轴向聚焦、异性高频谐振腔的设计、空间电荷效应等.研究了该加速器的调束技术,包括调束方案、诊断设备布局及径向靶测量的束流信息、物理图像.CYCIAE-100的主磁铁设计中,为降低磁铁和高频腔的加工难度而采用直边扇形磁极,为解决直边扇形磁极在大半径处的轴向聚焦力下降的问题,采用变气隙技术,从而有效提高轴向聚焦力.采用自行开发的基于PIC技术的宏离子模拟程序OPAL-CYCL进行了空间电荷效应的研究,结果表明,CYCIAE-100的极限流强为10 mA.