等时性回旋加速器中环形补偿线圈电流变化对引出束流性能的影响

本文报道了利用多丝束流剖面仪测量从等时性回旋加速器中引出束流的轴向性能,包括束流的中心位置、相对于磁场中心平面的夹角及束流在轴向的发射度。同时也测量了束流引出区环形补偿线圈中的励磁电流变化对引出束流性能的影响。测量结果表明,环形线圈电流变化对束流轴向发射度的影响较大,而对束流中心在轴向几何位置的影响较小。     

BRIF—ISOL系统离子源引出系统设计方法研究

BRIF-ISOL系统离子源的引出系统是决定引出束性能的关键部件。随着束流强度的变化，引出束附近的电位也会随之变化。本工作利用Pierce理论，研究了引出区电位分布随束流密度变化的关系。     

回旋加速器静电引出通道的计算

本文介绍三叶扇形可变能量等时性回旋加速器的束流静电引出通道的设计方法和特点,讨论了静电引出通道设计的基本粒子动力学要求,并根据静电通道的几何参数,对静电引出通道的单粒子运动方程作数值积分,从而确定了通道入口相对扇形磁场的合理方位角、通道分段的跨度及通道经向张口的程度,推导了单粒子运动方程等效的线性化简谐振荡方程。由束流光学的σ矩阵变换方法计算了通道入口的经向接受度及引出束包络,给出了引出束穿越边缘磁场的图象,证明在第一段静电通道内,引出束几乎正交地穿透等高斯线     

300MeV/A H_2~+可变能量超导回旋加速器束流引出物理设计研究

针对单粒子效应测试对质子束能量的要求,中国原子能科学研究院设计了一台300 MeV/A H_2~+超导回旋加速器,该加速器使用超导线圈实现主磁铁小型化,剥离引出H_2~+离子获得可变能量的质子束。通过调节剥离点位置和分析剥离后质子的轨迹与束流包络,对该加速器引出过程的束流动力学进行了研究,完成了引出过程的物理设计。结果表明,此台加速器可在205~240 MeV、265~300 MeV内连续变能量引出质子,在更低能量范围内有单能量点引出质子的能力。     

上海光源增强器注入引出系统物理设计

介绍了上海光源增强器注入引出系统物理设计.在增强器注入中,跟踪结果表明闭轨校正后增强器的水平和垂直接受度分别约为23πmm·mrad和37 πmm·mrad,均远大于直线加速器引出的9 πmm·mrad(3σ),可保证较大的注入效率.在增强器引出中,三个Bump铁能形成-个较好的凸轨,凸轨中心高度10 mm,选择将切割板置于距增强器中心轨道15 mm处,引出束中心22 mm.     

Calutron离子源离子束引出中的两次等离子体聚焦过程

从等离子体中引出离子束,是气体放电离子源研制中的一个重要课题。与电子枪中从阴极引出电子束相比,有类似之处,即离子离开等离子体后所遵从的基本物理规律(如泊松方程、运动方程和连续方程)和电子离开阴极后所遵从的基本物理规律是一样的。但是也有不同之处,最重要之点是电子枪中的阴极为固态发射体,发射面固定,而离子源中的等离子体却是位形可变的发射体。因此,使得从等离子体中引出离子束的物理过程,变得比电子枪复杂得多。经过不断的研究,人们逐渐认识了从等离子体中引出离子束时的等离子体聚焦过程。     

引出负离子的永磁边引出PIG源

介绍了一个可引出Ｈ、Ｏ、Ｆ等负离子的永磁边引出ＰＩＧ源。在１５ｋＶ引出电压下，可获得Ｏ＾－离子１３０μＡ，Ｆ＾－，离子７５μＡ，功率消耗分别约为１１０、２８０Ｗ。     

扇形聚焦迴旋加速器静电引出通道的设计

本文描述扇形聚焦回旋加速器静电引出通道的设计计算,给出了通道起始方位角位置、径向和轴向形状、接受度和引出电压的计算结果,列出了通道的典型几何和电参数。     

永磁端引出溅射PIG源进展

介绍了永磁端引出溅射ＰＩＧ离子源的进展状况，通常它可用于引出气体的与金属的单或多电荷离子，在２０－３０ｋＶ的引出电压下，可引出ｍＡ级的气体离子和数十微安的金属离子，功耗小于５０Ｗ。同时也可用于直接引出某些电子亲合势料强的气体元素，如，Ｈ，Ｏ，Ｆ等的负离子。     

AVLIS离子引出收集过程的初步研究

通过理论计算研究了１－Ｄ无碰撞ＡＶＬＩＳ离子引出过程，比较了交变场与恒定场对离子引出特性的影响，计算和分析结果表明等离子体离子密度≥１０７ｃｍ（－３），屏蔽效应存在，离子的引出在振荡中完成；对相同离子密度，随电场的增加，离子引出时间有饱和趋势，比较了脉冲场与恒定场的引出效果，结论是两者的引出效果一样，而采用脉冲场可消除斯塔克效应的影响。     

金属真空弧离子源引出强流离子束的数值模拟

为了引出更高强度、更高亮度的铀离子束,以满足重离子研究中心(Gesellschaft für SchwerionenforschungmbH,GSI)重离子同步加速器的需求,本文用三维的计算机程序KOBRA3-INP对金属真空弧离子源(Metalvapor vacuum arcion source,MEVVA)引出强流铀离子束在引出系统和后加速系统中的动力学特性进行了研究,讨论了离子源发射束流密度对引出束性能的影响.结果表明,束流损失主要发生在引出系统和后加速系统之间的漂移区;在假设漂移区束流被空间电荷中和的情况下,模拟结果和实验结果符合;在发射束流密度为180-230 mA/cm2范围内,经后加速的束流强度变化不大.     

Investigation of Arc Regulation of Hot Cathode Ion Source with Langmuir Probe

The neutral beam injector (NBI) is one of the main plasma heating methods for nuclear fusion devices. For the hot cathode high current ion source, the arc current and beam current tends to increase during the beam pulse. In order to gets long pulse beam extraction, the arc regulation technology is employed. The Langmuir probes are installed on the experimental advanced superconducting tokamak-NBI ion source, to feedback control the arc discharge and beam extraction. The experimental results show that, the long pulse of 100 s ion beam is extracted with beam energy of 30 keV with arc regulation. More the results are presented in this paper.     

Performance of Diagnostic Neutral Beam for the HT-7 Tokamak

Diagnostic neutral beam (DNB), combined with spectral diagnostics, is employed to measure the ion temperature in HT-7. The factors affecting the extracted beam are studied in the experiment for the high performance diagnostic neutral beam. A 6.5 A extracted hydrogen current at 43 keV of 100 ms was obtained after optimization. The extracted beam has a proton ratio as high as 40%, and can penetrate into the core plasma after neutralization to measure the ion temperature effectively.     

束流光学设计计算的最优化方法和计算机程序BOOP

描述了最优化技术在带电粒子束流传输系统设计计算中的应用。按照束流传输的矩阵理论和最优化方法，研制了用于束流光学系统优化设计的计算的程序，介绍了程序的特点和使用效果。     

Experimental Results of Ion Beam Extraction of High-Current Ion Source for EAST Neutral Beam Injector

The first campaign of ion beam extraction tests are completed for EAST NBI high current ion source. The hydrogen ion beam with beam voltage of 80 keV is extracted from tetrode accelerator system. During the experiment, the characteristics of arc discharge and ion beam extraction are studied. The arc power reaches 120 kW and the extracted ion beam power reaches 3 MW. The relationship of some key parameters of arc and beam are investigated, and the details are described in this paper.     

Beam dynamics study for a small, high current 14 MeV PET cyclotron

A 14 MeV high intensity cyclotron CYCIAE-14 dedicated to Positron Emission Tomography (PET) is under construction at China Institute of Atomic Energy (CIAE). Based on a set of basic technical requirements for the accelerator and its extracted beam, the cyclotron beam dynamics were studied and the results are presented. Static beam dynamics, beam motion inside the machine under imperfection conditions and beam behavior in the extraction process were also investigated. This work gives an in-depth view of the beam dynamics study, numerical simulation as well as the corresponding results and necessary analyses.     

双等源强流离子束分析

目前所使用的各种离子源,还不能产生具有完全单一荷质比的离子,所以,离子源所提供的离子束是包含多种离子组态的混合束。因此,要把离子加速到高能,就涉及到一个多动量离子束加速系统。在由电磁场(电磁组件)构成的强流带电粒子加速系统中,多动量离子束的加速和聚焦会产生许多缺陷与困难。在强流加速器中,提高所需离子的加速效率,减轻加速器的总负荷,是一个很重要的     

Mass spectrometry improvement on an high current ion implanter

The development of accurate mass spectrometry, enabling the identification of all the ions extracted from the ion source in a high current implanter is described. The spectrometry system uses two signals (x-y graphic), one proportional to the magnetic field (x-axes), taken from the high-voltage potential with an optic fiber system, and the other proportional to the beam current intensity (y-axes), taken from a beam-stop. The ion beam mass register in a mass spectrum of all the elements magnetically analyzed with the same radius and defined by a pair of analyzing slits as a function of their beam intensity is presented. The developed system uses a PC to control the displaying of the extracted beam mass spectrum, and also recording of all data acquired for posterior analysis. The operator uses a LabVIEW code that enables the interfacing between an I/O board and the ion implanter. The experimental results from an ion implantation experiment are shown.     

Energy loss of degrader in SC200 proton therapy facility

The proton beam energy determines the range of particles and thus where the dose is deposited. According to the depth of tumors, an energy degrader is needed to modulate the proton beam energy in proton therapy facilities based on cyclotrons, because the energy of beam extracted from the cyclotron is fixed. The energy loss was simulated for the graphite degrader used in the beamline at the superconducting cyclotron of 200 MeV in Hefei(SC200). After adjusting the mean excitation energy of the graphite used in the degrader to 76 eV, we observed an accurate match between the simulations and measurements.We also simulated the energy spread of the degraded beam and the transmission of the degrader using theoretical formulae. The results agree well with the Monte Carlo simulation.