Microbunching instability study in a linac-driven free electron laser spreader beam line
Microbunching instability study in a linac-driven free electron laser spreader beam line
复制标题
直线加速器驱动的自由电子激光散布器光束线中微聚束不稳定性研究
DOI：
10.1103/physrevaccelbeams.20.120701
复制
发表时间：
2017
影响因子：
1.7
通讯作者：
S. Spampinati
中科院分区：
文献类型：
--
作者：
S. Mitri;S. Spampinati
抑制微聚束不稳定性是自由电子激光器(FEL)的首要任务，其目标是产生具有很窄光谱带宽的强相干辐射。在将加速器连接到多条波荡器线路的多弯开关站线路中，这种不稳定性可能会有很大的增益。这项研究为在很大程度上不受微聚束生长影响的开关站光学设计提供了实用指导。以费米自由电子激光开关站为例，介绍了一种改进的光学设计，在保持电子束亮度的同时提供了单位微聚束增益。改进后的光学系统的增益的解析计算得到了模拟和实验结果的支持。
Suppression of the microbunching instability is a priority for free electron lasers (FELs) whose goal is production of intense coherent radiation with very narrow spectral bandwidth. The instability can have large gain in multibend switchyard lines that connect the accelerator to multiple undulator lines. This study provides practical guidelines for switchyard optics designs that are largely immune to microbunching growth. A case study of the FERMI FEL switchyard is illustrated, resulting in an improved optics design that provides a unity microbunching gain while preserving the electron beam brightness. The analytical computation of the gain for the improved optics is supported by simulations and by experimental results.