Speaker
Abstract
Aiming at the requirements of beam optics design and radiation physics analysis for synchrotron radiation storage rings, this study constructs a relativistic single-particle dynamics simulation platform based on the Modelica language. Leveraging the conciseness, object-oriented modeling capabilities, and excellent extensibility of Modelica, the platform aims to provide a unified tool for storage ring magnetic lattice modeling, particle tracking, and radiation effect analysis.
Regarding the physical model, the platform centers on the Landau-Lifshitz radiation reaction equation. It introduces a classical radiation damping correction term to the Lorentz force and employs a relativistic normalized coordinate system to mitigate numerical errors caused by the coexistence of physical quantities across multiple orders of magnitude, thereby improving computational stability and solving accuracy. In terms of software architecture, the platform utilizes Modelica's object-oriented modeling mechanism and connector features. A star-topology information bus is implemented for the global broadcasting of particle states and the automatic superposition of multiple fields. Additionally, class inheritance is utilized to support the plug-and-play functionality of various magnet components. The platform implements various field components, including quadrupole magnets, sextupole magnets, and radio frequency (RF) cavities, and features a built-in dual energy conservation verification mechanism based on the work-energy theorem and total energy balance.
Results demonstrate that the platform has successfully passed unit tests for pure magnetic cyclotron motion, electrostatic deflection, quadrupole and sextupole focusing, RF acceleration, and undulator trajectories. Furthermore, in multi-turn tracking simulations of the storage ring, it accurately reproduces the dynamic equilibrium between radiation damping and RF compensation, maintaining the energy conservation error within a reasonable range.
Overall, this study indicates that the platform can comprehensively perform single-particle dynamics simulations for synchrotron radiation storage rings, providing an efficient tool for the lattice design, algorithm verification, and prototype research of synchrotron light sources.
摘要
研究面向同步辐射储存环束流光学设计与辐射物理分析需求，构建了一种基于Modelica语言的相对论单粒子动力学仿真平台。该平台旨在利用Modelica语言的简洁性、面向对象建模能力及良好的可扩展性，为储存环磁结构建模、粒子追踪和辐射效应分析提供统一工具。
在物理模型上，平台以Landau-Lifshitz辐射反作用方程为核心，在洛伦兹力基础上引入经典辐射阻尼修正项，并通过相对论归一化坐标系减小多数量级物理量并存带来的数值误差，提高计算稳定性与求解精度。在软件架构上，利用Modelica的面向对象建模机制和连接器特性，通过星型信息总线实现粒子状态的全局广播与多场自动叠加，借助类继承支持不同类型磁铁元件的即插即用。平台实现了四极磁铁、六极磁铁、射频腔等多类场元件，并内置基于动能定理和总能量平衡的双重能量守恒检验机制。
结果表明，该平台通过了纯磁场回旋、静电偏转、四极和六极聚焦、射频加速及波荡器轨迹等单元测试，并在储存环的多圈追踪仿真中正确再现了辐射阻尼与RF补偿之间的动态平衡关系，能量守恒误差保持在合理范围内。
研究表明，该平台能够较完整地实现同步辐射储存环单粒子动力学仿真功能，可为同步辐射光源的晶格设计、算法验证与原型研究提供高效工具。
| 关键词 | 同步辐射；粒子追踪；Modelica；储存环 |
|---|---|
| Keywords | Synchrotron Radiation; Particle Tracking; Modelica; Storage Ring |
