中文摘要：

提出了一种对矩形离子阱进行仿真设计和优化的方法。该方法以数值分析为基础，对离子在矩形离子阱中的运动进行分析，得到相应的离子运动二阶微分方程。然后使用数值分析的Runge—Kutta法，对此二阶微分方程进行求解，可以得到理想状态下离子在离子阱中稳定的条件，从而完成对矩形离子阱的设计和优化。采用本方法，设计并优化了一种矩形离子阱，质量范围最大为260amu／e，使用乙醇作为目标样品，紫外灯源作为离子源，法拉第筒作为检测器，对该矩形离子阱进行了质谱实验，成功得到了质谱结果，验证了所提出的数值分析仿真优化方法的实用性和正确性。本方法简单易行，便于修改，针对性强，可对多个参数使用循环遍历的方式来寻找最优值，特别适用于对未知结构或参数的探索研究。以此方法为基础可开发离子运动仿真软件，有很好的应用前景。

英文摘要：

This paper introduces a method of simulating and optimizing the rectilinear ion trap （RIT）. It proves to be in principle by the verification experiment. According tothe numerical analysis, the method gets the second order differential equations, which describe the movements of ions in the RIT. The equations are solved by Runge-Kutta method and the conditions for stability of ion in the ion trap are obtained under ideal conditions. The conditions present the ability of catching and trapping the ions by the RIT. ARIT is optimized and designed according to the optimal conditions. The ethanol vapor is ionized by a UV discharge lamp and the RIT is used as a mass analyzer during the verification experiment. The ethanol ions are detected by a Faraday cup. The mass spectrum of ethanol is successfully obtained and the method is proved to be practical and correct. Mass range is up to 260 amu/e. The numerical analysis is simple, easy to modify and well-targeted. The loops can be used to find out the optimal structure and parameter, so the method is well suitable for the researches of RIT. The simulation software could be developed based on it. The method is of high maneuverability and possesses a vast range of application prospect.