论文标题
电子束纵相空间的分析回溯方法
An analytical backtracking method for electron beam longitudinal phase space shaping
论文作者
论文摘要
高亮度的许多应用，高度相对论的电子光束对纵向相空间质量有严格的要求。为了满足这些要求，加速器系统通常利用分散元素来操纵在加速度或通过集体效应期间获得的相关能量传播。这些系统中的许多免费变量使得找到最佳配置困难。我们在这里提出了一种分析方法，用于通过由加速度或漂移部分组成的加速器部分跟踪所需的最终纵向空间，然后是分散部分，包括相关集体效应的分析模型。这种回溯可以用作快速准确的工具，以优化和研究加速器系统的纵向空间动力学。在这里，我们将LCLS-II加速器视为示例情况，使用此方法在喷射器出口处找到加速器的构型和纵向相空间，从而导致峰值电流显着增加，同时保持狭窄的能量在加速器出口处的狭窄能量扩散。通过与优雅的模拟进行比较，测试了该方法的有效性，显示出良好的一致性。
Many applications of high brightness, highly relativistic electron beams carry strict requirements on longitudinal phase space quality. To meet these requirements, accelerator systems typically utilize dispersive elements to manipulate the correlated energy spread acquired during acceleration or via collective effects. The many free variables in these systems make finding an optimal configuration difficult. We present here an analytical method for tracking a desired final longitudinal phase space backwards through an accelerator section composed of an acceleration or drift section followed by a dispersive section, including analytical models of pertinent collective effects. This backtracking can serve as a fast and accurate tool for optimization and study of the longitudinal phase space dynamics of an accelerator system. Here, we consider the LCLS-II accelerator as an example case, using this method to find an accelerator configuration and longitudinal phase space at the injector exit that lead to a significant increase in peak current while maintaining a narrow energy spread at the accelerator exit. The validity of this method is tested by comparison with Elegant simulations, showing good agreement.
