物质世界的探测向着更高的时空分辨能力发展，未来的超高分辨率超快电子衍射、超快电子显微，以及X射线量子自由电子激光等技术或装置将成为探测物质微观超快过程的重要方向。极高的时间分辨率需要高亮度的超快电子束团，同时需要跨度较大的占空比调节范围以适应更加多样化的物质研究领域。本课题基于中物院高平均功率太赫兹自由电子激光（CTFEL装置）现有的光阴极直流高压电子枪和连续波超导直线加速器组成的注入器，拟针对占空比大范围可调的超快电子束的获得及测量这一关键物理问题展开系统深入的理论与实验研究，主要研究内容包括：①基于差分进化人工智能方法的多参数多目标超快电子束产生的束流动力学优化研究；②设计宏脉冲占空比跨度为1E-6~1E-2，微脉冲纵向长度~200fs的实验验证平台；③基于人工智能方法和相干渡越辐射方法结合的超快电子束纵向长度测量研究。本课题的研究将为高重频高占空比的超快电子束应用提供技术储备。

The detection of materials is developing towards higher spatial and temporal resolution. New technologies or facilities, such as ultrafast electron diffraction (UED), ultrafast electron microscopy (UEM), and X-ray quantum free electron laser (XFEL), and so on, will become more and more important for the the detecting of the microscopic ultrafast process of matters . Extremely high time resolution requires high-brightness ultrafast electron bunches, while requiring a wide range of duty cycle adjustments to accommodate more diverse material research areas. .This research will be mainly carried out on the high-average power terahertz free electron laser (CTFEL) of the China Academy of Engineering Physics (CAEP). The CTFEL’s injector consists of a high-voltage photocathode DC gun and a continuous wave superconducting linac. Based on the injector, there will be some theoretical and experimental research on the key physical problem of obtaining and measuring ultrafast electron beams with adjustable duty cycle. The main research contents include: ① Beam dynamics optimization based on differential evolution artificial intelligence method for multi-parameter multi-objective ultrafast electron beam generation; ② Design macro-pulse duty cycle from 1E-6 to 1E-2, micro-pulse longitudinal length ~200fs with experimental verification; ③Ultrafast electron beam longitudinal length measurement with artificial intelligence method and coherent transit radiation method. The research of this project will be of great importance for the application of ultrafast electron beam with high repetition and high duty cycle.