上海EBIT装置漂移管组件研制

漂移管组件为EBIT提供约束离子的轴向电势阱,是EBIT装置的核心区域.组件工作在低温、强磁场、高电压、超高真空的环境中,这对工程设计提出了很高的要求.本文介绍了上海EBIT装置的电势阱设计、漂移管组件的结构设计和一些特殊工程问题的处理方法,并对组件进行了低温和高压试验.本文的研究工作,对上海EBIT装置的成功研制有着重要的意义,目前上海EBIT可以稳定运行在100kV/110mA.     

用于EBIT装置的小型MEVVA源及其离子注入实验

为给上海电子束离子阱(Electron Beam Ion Traps,EBIT)装置提供低电荷离子,我们研制了小型金属蒸汽真空弧(Metal Vapor Vacuum Arc,MEVVA)离子源,可产生多种金属以及半导体材料的低电荷离子.本文介绍小型MEVVA离子源的特性及其在上海EBIT装置上的离子注入实验.实验结果显示,合理控制注入参数可以使注入并被束缚在EBIT中的离子数密度达到108～109/cm3.     

上海EBIT动态控制电路设计

通过对上海EBIT装置离子注入引出系统的分析,采用FPGA为控制逻辑单元来设计EBIT装置的动态控制电路,实现了对EBIT装置中离子“注入-引出-电离”的动态控制。上海EBIT动态控制系统包括了基于FPGA的控制电路的设计和用户控制界面的设计。采用FPGA来设计EBIT动态控制系统,提高系统的控制速度和精度。     

上海EBIT装置的机械准直

采用准直望远镜对上海电子束离子阱(EBIT)装置进行机械准直,制定了合理的准直方案,设计了高精度的机械调节机构和良好的准直工艺,并进行了试验.通过准直,各组件的位置精度均达到设计指标,目前上海EBIT可以稳定运行在高压100keV和束流110mA的条件下.     

SDUV-FEL真空联锁保护系统

上海深紫外自由电子激光装置(SDUV-FEL)真空联锁保护系统基于EPICS系统框架,通过可编程控制器实现了对不同运行模式下真空系统的有效保护.同时,通过嵌入式系统构成的IOC控制器及网络通讯模块,实现了对装置真空状态的远程实时监控.系统已在级联HGHG FEL实验中使用,运行结果证明了系统的高稳定性和可靠性.     

上海电子束离子阱低温超导磁体系统的研制

介绍了上海电子束离子阱(Electron beam ion trap,EBIT)装置低温超导磁体系统的研制过程和测试结果.超导磁体由一对上下布置的Helmholtz线圈组成,中心最大磁场强度可达5.3 T,两线圈的峰值磁场偏差小于3×10-4 T,在中心轴线上±10mm内磁场均匀度好于2×10-4,磁场衰减率在8 h内小于1×10-4.低温系统采用双冷屏结构,通过二级G-M制冷机冷却冷屏来降低液氦的蒸发量.系统液氦灌注达到平衡后,液氦的平均蒸发量为1.1 L/h,基本满足了用户的要求.     

HL-1M中性束注入器真空烘烤温度监测

为了进一步改善中性束注入器真空系统的性能,满足装置真空度的要求,在系统与装置进行真空连接后,需要对其进行真空烘烤去气。而系统真空密封材料的耐热老化性、烘烤加热面及系统焊缝的真空密封都要求对烘烤温度加以限制,以免影响系统的真空密封性能。因此,对烘烤温度进行测量和控制就显得尤其重要。     

一种穆斯堡尔谱测量用的样品控温装置

我们研制成一种穆斯堡尔谱测量用的样品自动控温装置,并用该装置对不同样品分别在各种设定温度下测量了穆斯堡尔谱,得到了较为满意的结果。装置由三部分组成:1)JWK-702温度控制装置,用以测温和自动控制加热器功率;2)液氮罐,用以储存液氮等冷却剂;3)冷指系统。是一个真空室,紫铜样品架在真空室内,与伸出真空室外的紫铜棒相连;紧靠样品架设有测温铂电阻和加热器,真空室的外壁设有真空阀门和绝缘子,     

法兰环缝局部真空电子束焊接技术研究

叙述了局部真空电子束焊接的特点及其在国防工业和民用工业的应用前景，叙述了国内外局部真空电子束焊接的发展状况，介绍了自行研制的法兰环缝局部真空电子束焊接装置和它的主要技术指标，以及该设备研制已突破的关键技术。     

旋转式轻元素X射线荧光光谱测量装置的设计

设计了一种旋转式轻元素X射线荧光光谱测量装置。该装置利用高性能硅漂移探测器(SDD)在真空条件下对样品中轻元素进行测量。该装置主要由真空腔和外围控制电路两部分组成:真空腔样品托盘一次可容纳10个样品,并可任意切换进行测量;外围电路主要由主控单元、电源模块、电机驱动模块、气压模块等组成,主要实现被测样品切换、滤光片切换、气泵的开启或停止以及对气压值实时读取等功能。该装置具有体积小、成本低、测量周期短和工作效率高等特点,满足野外轻元素X射线荧光光谱测量的要求。     

The present status of the Shanghai electron beam ion trap

1Construction of the device EBIT(electron beam ion trap)is an ideal device to produce,trap,and study highly charged ions.Basi-cally it can provide any charge states of any element in the periodic table.After the first development at the Lawrence Livermore National Laboratory in1986,[1,2]EBITs have been constructed in Oxford,[3]NIST,[4]Tokyo,[5]Berlin[6]and Freiburg[7](now moved to Heidelberg).Shanghai EBIT project was launched at the beginning of the year of2002.[8,9]The conceptual d…     

A K-CELL injection system for SH-PermEBIT

In this paper,we report a newly developed Knudsen Cell injection system for SH-PermEBIT.This technique can overcome disadvantages of introducing organometallic gases and wired probes into EBIT and provide steady continuous injection.A specially designed vacuum line is used to ensure that the Knudsen Cell satisfies the vacuum level of SH-permEBIT.Using this system we successfully injected ytterbium into the SH-pcrmEBIT and recorded a spectrum in the visible wavelength region.     

A multi-parameter data acquisition system for the collision research platform at Shanghai EBIT

In this work we describe a multi-parameter data acquisition system (DAQ) which has been developed for the Shanghai EBIT.This system is operated at the collision research platform which includes a recoil-ion momentum spectrometer (RIMS).We have employed DAQ based on the VME system,which is a very fast developing system within the RIMS community,and with which we can reach data transfer rates of up to 160 Mb.s-1.The software developed for DAQ based on UnisDX-XP is also described.     

Implementation of effective control system for variable-included angle plane-grating monochromator

The variable-included angle plane-grating monochromator is a homemade key equipment of the scanning transmission X-ray microscopy (STXM) beamline at Shanghai Synchrotron Radiation Facility (SSRF).Monochromatic light of various wavelengths is achieved by an effective control system that handles the rotation of the plane mirror and plane grating mounted in a high vacuum chamber.M511.DDB made by PI Corp.is used as motion stage which has a DC servo motor controlled by a C862 controller based on RS232 protocol.The software platform of STXM is EPICS,so the local control functions are implemented by LabVIEW program to satisfy physics control.For the remote control functions,the program is integrated into EPICS with ShareMemoryIOC.Experimental tests show that the repeat precision of motion control is less than 0.2μm,which meets the control demand.     

Beam dynamics design of an SP-FEL compact THz source

In recent years, people are looking for a new compact THz source with high emission power, one potential choice is to build small accelerator with Smith-Purcell radiation. The main difficulty is how to obtain high quality electron beam. In this paper, the beam dynamics design of a compact THz source is presented. The electron beam is produced by an electron gun and compressed by permanent magnets. The electron gun is similar to the Shanghai EBIT,but permanent magnets are used, instead of the superconducting magnets in Shanghai EBIT. With this design, we can reduce the size and cost of the whole device. Poisson/Pandira was employed to simulate and optimize the magnetic field. Egun was used to simulate the beam trajectories from the electron gun to the collector. Within 2 centimeters around the center of longitudinal magnetic field, the calculation showed that the beam satisfies to our design aim.     

Touschek lifetime study based on the precise bunch-by-bunch BCM system at SSRF

Continuous tracking of bunch charges is the key to maintain stable operations in a storage ring in top-up mode. Recently, a precise bunch-by-bunch beam-current measurement(BCM) system has been developed at the Shanghai Synchrotron Radiation Facility. To avoid the influence of longitudinal oscillation on the amplitudes of the sampling points, a method called two-point equilibrium sampling is introduced. The results, obtained during routine operation time, show that the relative resolution of the measurement of the bunch charges is better than 0.02%.With this high resolution, the new BCM system is able to monitor the bunch-by-bunch beam lifetime. By using the filling pattern information, the Touschek lifetime and the vacuum lifetime can also be calculated. In this paper, the principle of the new method and the experiments is presented in detail.     

上海光源工艺冷却水系统加热器设计

介绍了上海光源(SSRF)工艺冷却水系统加热器的选择和设计方法,加热器发热量的计算和加热器变压器的连接方式选择.说明了控制电加热的方法和电加热使用后对系统稳定的作用.