用于兰州彭宁离子阱的多反射飞行时间质量分析器的设计和优化  

Design and Optimization of A Multi-reflection Time-of-flight Mass Spectrometer for LPT

作　　者：王永生[1,2,3] 田玉林 王均英[1] 周小红 黄文学[1] 

机构地区：[1]中国科学院近代物理研究所,兰州730000 [2]中国科学院大学物理科学学院,北京100049 [3]兰州大学核科学与技术学院,兰州730000

出　　处：《原子核物理评论》2017年第3期624-629,共6页Nuclear Physics Review

基　　金：国家自然科学基金资助项目(11605268;11405243;11675224);国家重点基础研究发展计划项目(973计划)(2013CB834400)~~

摘　　要：MRTOF-MS是最近几年发展起来的新型质谱仪,较传统的飞行时间质谱仪而言,MRTOF-MS质量分辨本领更高。开发了一种用于MRTOF-MS设计的新方法,该方法由参数设置部分和离子运动计算部分共同组成;分全局搜索和局部细化两个步骤,可用于优化MRTOF-MS的几何构型、计算不同条件下的最佳电压设置组合。基于这种方法,设计了一种机械结构与国际上同类设备不同的MRTOF-MS,该设备可用于高精度原子核质量测量,也可用于快速质量选择,为LPT提供纯净的目标核。通过优化,确定了其几何参数和电压参数,讨论了不同电极上的电压偏差对质量分辨本领的影响,定量地分析了电源的精度要求。优化结果表明:MRTOF-MS的最佳漂移长度约为400 mm;在最佳电压设置下,当40Ar^(1+)的总飞行时间为6.5 ms时,其质量分辨本领可达1.3×10~5;要求电源精度好于50 ppm,最好达到20 ppm。Multi-reflection time-of-flight mass spectrometer（MRTOF-MS） has been developed as a new device which has a higher mass resolving power than traditional mass spectrometers in recent years. A new method including two sub-procedures, global search and local refinement, has been developed and applied to design a MRTOF-MS. It consists of two components, parameter configuration and ion motion simulation, and can be used to optimize the geometries of the spectrometer and the potentials applied on the electrodes to achieve the optimum in different conditions. By using this method, a different type of MRTOF mass analyzer has been designed for mass measurements and isobaric separation for Lanzhou Penning Trap（LPT）. The geometry of this analyzer and potentials at different electrodes have been optimized, and the relations between resolving power and potentials and the power accuracy requirements have been analyzed and discussed quantitatively. The simulation shows that the optimal length of the drift-tube is about 400 mm; the maximal resolving power of 1.3 × 10^5 has been achieved with a total time-of-flight of 6.5 ms under the optimal potentials for an ion species of40 Ar^1＋; and the inaccuracy of the potentials applied to the mirror electrodes must be less than 50 ppm or preferably 20 ppm.

关 键 词：飞行时间质量分析器 多反射 质量测量 同质异位素在线分离 

分 类 号：O571.53[理学—粒子物理与原子核物理]