共查询到18条相似文献,搜索用时 89 毫秒
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加速管是加速器设计的核心部分。常规设计加速器的俘获效率只能达50%左右,1/2的电子都损失在加速管内,丢失的电子会轰击加速管管壁,产生轫致辐射、腔体发热量增加、真空变坏等许多负面影响。采用等梯度加速结构,相速沿加速管呈线性增加,调整相速变化规律及加速管腔体的尺寸参数,设计的加速管最终俘获效率提高到90%以上,同时平均加速梯度没有因此降低,加速管总长度未增加。 相似文献
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对400 kV强流中子发生器进行了物理设计。采用Poisson/Superfish软件对中子发生器高压电极和加速管的电场分布进行了模拟,结果显示,各关键区域的空间电场最大值远低于击穿电场限值。以强流束旁轴包络方程为基本模型,发展了强流束传输系统束包络的计算机模拟程序IONB1.0,模拟了中子发生器传输系统中40 mA的D束流包络。结果显示,设计方案中所采取的两间隙高梯度加速结构有较强的聚焦性能,能有效抵消强流束空间电荷效应造成的束流发散,加速管出口处的束包络半径约3 cm,由加速管出口处的空间电荷透镜和三重四极磁透镜组成的传输系统能将束流聚焦在约140 cm处的靶上,且束斑直径小于2 cm。 相似文献
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加速管是加速器设计的核心部分。常规设计加速器的俘获效率只能达50%左右,1/2的电子都损失在加速管内,丢失的电子会轰击加速管管壁,产生轫致辐射、腔体发热量增加、真空变坏等许多负面影响。采用等梯度加速结构,相速沿加速管呈线性增加,调整相速变化规律及加速管腔体的尺寸参数 相似文献
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对不同能量、不同质量数、不同初始条件的入射束和有无空间电荷效应的离子束流在高梯度加速管中的传输进行了计算,并讨论了一些影响加速管聚焦作用的主要因素,计算结果与实际情况相符。 相似文献
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一、引言我们自行研制的2.5MV静电加速器加速管长2.2m,直径270mm。要求加速管在内部处于10~(-6)Torr真空,外部充以10—13atm、承受大于12kV/cm电压梯度的情况下,能稳定可靠地加速带电粒子流,并能以较高的传输效率引出。这就必须作到: 1.构成加速管的各元件具有较高精度。 2.每一元件符合真空卫生要求。各电极具有较高的光洁度(达到镜面光)。 3.用玻璃作绝缘环时,内应力尽量小,无气泡,无杂质,有较高的机械强度和耐电压能力。 4.每一胶面要有良好的密封性能。在保证密封的前提下,胶层越薄,胶越少越好。 相似文献
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ISOCELE Collaboration P. Kilcher J. C. Putaux J. E. Crawford H. Dautet H. T. Duong F. Le Blanc J. K. P. Lee J. Obert J. Oms J. Pinard B. Roussi re J. Sauvage G. Savard G. Thekkadath 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》1992,70(1-4):537-539
A new experimental setup PILIS II has been installed on-line with the ISOCELE isotope separator (IPN, Orsay). The mass-separated ions are slowed from 30 kV to 500 V and implanted on a graphite collecting disk. The atoms are then thermally desorbed at the implantation region by Nd: YAG laser pulses and selectively ionized by three laser beams. The ions created are mass identified by a time-of-flight (TOF) system. Two versions of the TOF system with accelerating voltages of 1.5 and 30 kV were used to carry out hyperfine structure measurements. With the 30 kV system we obtained an overall detection efficiency of 1.4 × 10−5. First measurements were performed on very light gold and platinum isotopes. It has been shown that PILIS II is well adapted to study very short half-life isotopes (
). 相似文献
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文章介绍兰州重离子加速器冷却储存环主环用于加速粒子的高频加速系统。加速系统的频率范围为0. 25~1.7MHz,最高峰值电压为8.0kV。高频腔体的固有谐振频率通过调节绕在腔体加载的铁[JP2]氧体材料上的偏磁电流来改变,所加载的铁氧体材料为600HH。高频腔体内的真空度达到3×10-9Pa,高频发射机的最大输出功率为30kW,高频系统的控制采用基于PCI总线技术,它提供所有高频系统控制及监测功能。 相似文献
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LUO Rongrong 《等离子体科学和技术》2013,15(3):303-306
In this paper, surface modification of the strut dowel used in ITER PF support is reported. Different ions (nitrogen/titanium) with different doses are implanted into the surface of strut dowel. The result of Auger Electron Spectroscopy (AES) indicates that nitrogen can be implanted more deeply than titanium under the implantation condition of 60 kV accelerating voltage and a dose of 8x1017/cm2 nitrogen. Surface Micro Hardness (SMH) and wear resistance are improved remarkably. Further SEM observation shows that there are no obvious scratches and damages after wear test. 相似文献
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中国原子能科学研究院目前正在研制一台用于质子治疗的230 MeV超导回旋加速器。本文设计用于230 MeV超导回旋加速器的高频腔体,其采用螺旋结构,由4个腔体组成,高频系统采用二次谐波加速,高频腔体工作频率约71.25 MHz。4个半波长的电容加载型谐振腔工作于Push-Pull模式,其中两个腔体在中心平面直连,另外两个腔体在中心区下方使用过桥连接,两组腔体之间存在电容耦合,相差180°。在腔体的设计过程中,采用计算机对4腔体进行联合仿真,经优化后,腔体加速电压分布在中心区部分的为75 kV,大半径部分的提升至110 kV,腔体的无载品质因数仿真结果约8 800。为保证腔体的高频性能,腔体主体材料采用无氧铜材料,其加工难度在于上、下外壳需分别焊接成一个整体,同时要控制其形变量。目前,腔体已完成加工,单个腔体的无载品质因数的测试表明,腔体的无载品质因数均好于7 000,满足要求。 相似文献
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This paper describes the design, construction, and performance of a time base generator for use with a cathode ray tube capable of displaying fractional nanosecond transients. The generator was designed for use with a traveling wave cathode ray tube having a simple electrostatic time base deflection structure. When operating into the deflection plates (total capacitive load of 25 pF), the generator produced a total ramp excursion of -4 kV with a maximum average slope of about -450 V/ns. with a maximum repetition rate of 10 kHz. The ramp slope may be decreased continuously by a control voltage. The generator may also be operated into a 50 ohm load for the production of a -750 V transition with a 10%-90% transition time of 4.8 ns. 相似文献
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V. Nassisi M.V. Siciliano 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2011,269(24):2919-2923
In this work, we present the experimental results of a laser ion source (LIS) implemented for ion accelerators. A KrF excimer laser beam operating at 248 nm was focused on a solid target mounted inside a vacuum chamber in order to obtain the plasma. The laser energy was fixed at 11.5 mJ/pulse. The ion components of the plasma were extracted and accelerated up to 160 keV per charge state by a double gap system formed in two different stages. The beam cross section was circular, 1.5 cm in diameter. Using Cu and Y disks, as laser targets, we produced ion beams containing 1.2 × 1011 ions/pulse (0.7 × 1011 ions/cm2). Applying a total accelerating voltage of 60 kV we obtained an increase in ion dose up to 3.4 × 1011 ions/pulse, (2 × 1011 ions/cm2) for the Cu target and up to 6.3 × 1011 ions/pulse (3.5 × 1011 ions/cm2) for the Y target. The characterization of the plasma was performed using a Faraday cup for the electromagnetic properties, and a pepper pot system for the geometric ones. At 60 kV accelerating voltage and 5.5 mA output current the normalized beam emittance resulted in 0.22 π mm mrad for the Cu target, while under the same accelerating voltage, but with 7.4 mA output current, the normalized beam emittance resulted in 0.14 π mm mrad for the Y target. 相似文献