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Dynamics and Device for Nano-Second Ion Beam Compression at CSRm
No full text兰州重离子加速器冷却储存环的成功建成不仅为我国开展基础研究提供条件，而且会也为应用研究提供先进的实验条件和新的科学机遇。
目前，经过CSRm加速腔加速后的重离子束流无法满足高能量密度物理（涉及重离子驱动惯性约束核聚变新能源前期研究）和重离子聚变等基础研究所要求的高束流强度和纳秒量级短脉冲长度的需要，必须要对其束流进行纵向压缩。鉴于成本和有效性考虑，采用束团非绝热压缩方法对束团进行纵向压缩。因此，用于束团纵向非绝热压缩装置的研制也成了必然。
利用K-V包络方程对CSRm典型能量为250MeV/u、初始纵向束团长度为200ns，初始动量分散为5×10-4的238U72+离子束团的纵向非绝热压缩过程进行了束流动力学模拟，给出了束团在压缩过程中所要求的高频电压以束流相关参数的变化。
利用等效RLC电路方法和CST软件对纳秒级重离子束团获取装置---CSRm纵向束团非绝热压缩腔进行了计算和模拟。根据束团非绝热压缩理论以及CSRm储存环直线段长度的限定，因此，所要求的高频腔应该具有足够高的高频场梯度。本论文研究了一种采用新型软磁合金材料加载的高梯度高频腔，详细介绍了加载材料新型软磁合金的高频特性，研究了此高频腔所能达到的最大高频场梯度，模拟了其工作频率范围、品质因数等特性
Investigation on Test Methods of Single Event Effects in SRAM
No full text本课题从 CMOS SRAM 的单粒子效应机理出发，研究单粒子翻转和单粒子闩锁的检测
方法，建立了一个功能较为完善、操作简单的单粒子效应检测平台。它驱动被测 SRAM
在重离子辐照环境下工作，监测 SRAM 的工作状态，甄别单粒子闩锁和单粒子翻转发生
与否，并且能对实验数据进行初步处理分析，生成测试报告。2009 年 12 月下旬至 2010
年 3 月上旬，该检测平台在兰州重离子加速器上对 IDT71256 SRAM 开展了 3 次单粒子效
应辐照实验， 获得了一批实验数据， 达到了预期目标。 SRAM 单粒子效应检测方法的研究，
为我所科研人员开展半导体器件单粒子效应机理研究提供了基本条件
Research and Design of Digital Power Supply Regulator Based on
No full text改善电源系统的性能对提高加速器的束流品质和运行效率起着重要作用。
数字控制因其具有在线可编程能力、可靠性高、集成度强等优点，成为当今加
速器电源技术发展的趋势。本文针对加速器电源的特殊要求提出了基于FPGA的
数字电源调节器的实现方案。
基于H桥拓扑结构的电源运行于倍频斩波模式时可以输出双极性的直流/脉
冲电流波形，很适合加速器系统四极铁、六极铁等运行的需要。本文分析了 H
桥倍频斩波模式的工作原理，并用matlab对电源系统进行建模仿真，研究了不
同的控制策略对模型性能的影响。
选用Altera的基于NiosII的SOPC平台来进行数字电源调节器的设计。以
现场可编程门阵列为控制核心，采用片上可编程系统的设计思想，并针对加速
器电源的特殊要求设计了数字调节器。电源样机的测试结果表明电源性能基本
满足加速器要求。
该数字电源调节器的实现，为下一步研发高精度的加速器数字电源提供了
重要的参考价值
The development and construction of Time-of-Flight detector for isochronous mass measurement
No full textHIRFL-CSR 工程的顺利完工，使在 CSRe 上精确测量原子核的质量成为可能。利用
CSRe 作为等时性质谱仪，结合 RIBLL2 作为碎片分离器，可精确测量短寿命的、远离稳
定线的原子核的质量。为了利用等时性方法对原子核的质量进行精确测量，必须研制一
种具有高探测效率、低能损、好的时间分辨等特点的飞行时间（ToF）探测器来精确测
量离子在 CSRe 中的回旋周期。根据实验要求，我们设计了一种二次电子在匀强磁场中
偏转 180°的 ToF 探测器，利用 SIMION 对探测器的结构进行了模拟优化。然后根据设计
结果，加工制作了 ToF 探测器、磁铁、探测器支架等。在实验室中，利用α 源 239
Pu 对组装好的探测器的探测效率、时间分辨等进行了测试。探测器对α 离子的探测效率达 54
％，时间分辨约为 116 ps（FWHM）。此外，探测器也被安装在 CSRe 上进行等时性质
量测量，此次实验的主要目标是精确测量 65As 等丰质子核的质量。分析实验数据可知，
实验中探测器的最大探测效率可达 70％，时间分辨约为 118 ps（FWHM）。还分析了实
验中 Z 不同的核在探测器上产生的信号幅度，发现不同核在探测器上产生的信号平均幅
度大小与核的Z密切相关， 这是由于Z不同的核在碳膜上发射的二次电子数不同导致的。
因此，可利用 Z 不同的核在探测器上产生信号的平均幅度不同来进行 Z 鉴别。这种新方
法首先被用来鉴别那些由于荷质比非常接近而难以用回旋周期进行鉴别的核
THE ISOCHRONOUS MAGNETIC FIELD OPTIMIZATION OF HITFIL CYCLOTRON*
No full textAbstract<br />A new project named HITFiL（Heavy Ion Therapy<br />Facility in Lanzhou）is being constructed. In this project,<br />a 7Mev C125+ cyclotron is selected as the initial injector<br />providing a 10 uA carbon beam. The isochronous<br />magnetic field optimization of the cyclotron is introduced<br />in this paper. Optimization result shows that the<br />deviations between calculation values and theory are<br />smaller than 5Gs. In the design process, the sofware<br />OPERA has been utilized for the field calculation and<br />optimization
DEVELOPMENT OF POWER SUPPLIES FOR 3-Ф, 240 KW RF SYSTEM WITH CROWBAR PROTECTION FOR SUPERCONDUCTING CYCLOTRON AT VECC
No full textRF system of K-500 Super-conducting Cyclotron at<br />VECC is a complex three phase system operating in the<br />frequency range of 9 MHz to 27 MHz with maximum<br />acceleration potential of around 100KV feeding to each of<br />three Dee cavities placed in median plane of cyclotron<br />120º apart through coupling capacitors. Each phase<br />consists of chain of amplifiers and resonator operating in<br />synchronization and at final stage of each phase, high<br />power water cooled Tetrode Tube (Eimac4CW150,000 E)<br />is used as high power amplifier each capable of delivering<br />80 KW of RF power. Individual power supplies for<br />biasing Anode, Filament, Grid and Screen for all three<br />high power Tetrode Tubes are designed and developed in<br />house. Anode supply is common to all three tubes, rated<br />at 20KV, 22 Amp, 450 kW along with fast acting crowbar<br />protection using Ignitron. All these power supplies are<br />commissioned and have been in operation for more than<br />one year successfully. This paper describes about the<br />technical aspects of the power supplies for RF Amplifier<br />Tubes and special features of protection systems
PRESENT STATUS OF JAEA AVF CYCLOTRON FACILITY
No full textIn order to supply ion beam stably we have recently<br />constructed an all-permanent-magnet type ion source. Ion<br />beams such as H, O and Ne were produced stably. A<br />beam attenuation system with metal meshes has been<br />improved. By using new meshes with denser hole<br />arrangement and lengthening the space of meshes, beam<br />intensity can be controlled more precisely with<br />maintaining the beam profile. The power supplies of the<br />magnet coils used in the cyclotron were modified to<br />stabilize the coil current with the stability ΔI/I of the order<br />of 10-6. In addition, developments of new irradiation<br />techniques such as quick change of microbeam by<br />cocktail beam acceleration technique and large-area<br />uniform beam irradiation using multipole magnets are in<br />progress.IMP;Chinese Academy of Science
ION SOURCE RELATED RESEARCH WORK AT JYFL*
No full text<p>In this article the work of the JYFL ion source group<br />will be presented. New bremsstrahlung measurements<br />were carried out in order to compare the results with<br />different electron heating models. Especially attention<br />was paid to study the effect of different heating<br />parameters on the evolution of bremsstrahlung energy. A<br />project to obtain new information about the ion<br />temperatures and their time evolution has been initiated.<br />The study will be performed using spectroscopic<br />techniques measuring the ion temperature from the<br />Doppler broadening of emission lines. The objective is to<br />obtain accurate information about the evolution and the<br />behaviour of highly charged ions in the ECRIS plasma.<br />The work of the JYFL ion source team also includes<br />frequency tuning experiments, beam quality experiments<br />and tests with a so-called collar structure mounted on the<br />plasma electrode. The beneficial effect of collar was first<br />tested and noticed with the ECR ion sources by the KVI<br />ion source group and has been shortly confirmed at JYFL.<br />The JYFL ion source group is also developing a low<br />power electron gun for the needs of spacecraft<br />applications. The results of the development work can<br />possibly be applied also with the ion sources in order to<br />increase the density of cold electrons.</p>IMP;Chinese Academy of Science
REVIEW ON CYCLOTRONS FOR CANCER THERAPY
No full textThe science and technology of proton and carbon
therapy was initially developed in national and university
laboratories. The first hospital based proton therapy
facility was built at Loma Linda University with the help
from Fermilab. After this initial phase, and starting with
the tender for the proton therapy system at MGH, many
proton and carbon beam facilities have been ordered from
industry and built. Industrially made proton and carbon
therapy facilities represent today the vast majority of the
installed base.IMP;Chinese Academy of Science
DESIGN OF IBA CYCLONE®11 CYCLOTRON MAGNET
No full textThe development of a new Cyclone®11 11MeV Hcyclotron
is in progress at IBA. Such machine is designed
for the production of radionuclides for nuclear medicine.
This cyclotron is based on the existing Cyclone®10 that
has been boosted to more than 11 MeV with as minor as
possible change to the Cyclone®10 geometry. At first, the
magnetic field has been raised by a small reduction of the
valley depth. Additionally, the main coil current has been
increased. Pole edge milling has been used to obtain the
isochronous magnetic field shape. Beam optics in the
magnet is excellent. Extraction is ensured by means of
stripper foils mounted on carousels located at different
azimuths allowing installation up to eight targets and dual
beam extraction.IMP;Chinese Academy of Science