Perosa Giovanni, Di Mitri Simone
Dipartimento di Fisica, Università degli Studi di Trieste, Piazzale Europa 1, Trieste, Italy.
Elettra-Sincrotrone Trieste S.C.p.A., S.S. 14-km 163.5 in AREA Science Park, 34149, Basovizza, Trieste, Italy.
Sci Rep. 2021 Apr 12;11(1):7895. doi: 10.1038/s41598-021-87041-0.
The possibility to predict, characterize and minimize the presence of spurious harmonic content in the longitudinal profile of high brightness electron beams, namely the microbunching instability, has become vital to ensure accurate modeling and reliable operation of radiofrequency and plasma-based linear accelerators such as those driving free-electron lasers. Recently, the impact of intrabeam scattering (IBS) on the instability has been experimentally demonstrated by the authors. This work complements that experimental study by extending existing theories in a self-consistent, piece-wise calculation of IBS in single pass linacs and multi-bend transfer lines. New expressions for the IBS are introduced in two different semi-analytical models of microbunching. The accuracy of the proposed models and the range of beam parameters to which they apply is discussed. The overall modeling turns out to be a fast comprehensive tool for the optimization of linac-driven free-electron lasers.
预测、表征并最小化高亮度电子束纵向分布中杂散谐波含量（即微聚束不稳定性）的可能性，对于确保诸如驱动自由电子激光器的基于射频和等离子体的直线加速器的精确建模和可靠运行至关重要。最近，作者通过实验证明了束内散射（IBS）对该不稳定性的影响。这项工作通过在单通直线加速器和多弯传输线中对IBS进行自洽的分段计算来扩展现有理论，从而对该实验研究进行补充。在两种不同的微聚束半解析模型中引入了IBS的新表达式。讨论了所提出模型的准确性及其适用的束参数范围。总体建模结果表明它是用于优化直线加速器驱动的自由电子激光器的快速综合工具。
