基于相干渡越辐射的束团长度测量研究  

Measurement study of electron bunch length based on the coherent transition radiation

作　　者：边宇[1,2] 张文艳[1] 刘波[1] 王东[1] 

机构地区：[1]中国科学院上海应用物理研究所嘉定园区,上海201800 [2]中国科学院大学,北京100049

出　　处：《核技术》2017年第1期6-11,共6页Nuclear Techniques

摘　　要：电子束团长度是束流诊断中的重要参数,基于相干渡越辐射(Coherent Transition Radiation,CTR)的测量方法是一种简单易行的高时间分辨率测量方法。本文调研并分析了不同电子束团长度测量方法的优缺点,选择基于CTR方法作为主要研究方向,主要针对上海深紫外自由电子激光实验装置(Shanghai Deep Ultra-Violet Free Electron Laser,SDUV-FEL)和X射线自由电子激光试验装置(Shanghai X-ray Free Electron Laser,SXFEL)进行了实验方案设计和模拟分析。结果表明,通过合理的参数选择和方案优化,用该方法可对飞秒至皮秒范围内的束团长度进行测量,时间分辨率能到达飞秒量级,满足SDUV-FEL的实验需求和SXFEL的工程需求。Background： Longitudinal electron bunch length is an important parameter in accelerator beam diagnostics. It plays a significant role in single-pass free electron lasers, since the high-gain Free Electron Laser （FEL） process depends strongly on a high peak current of the electron bunches. Purpose： It is necessary to measure the electron bunch lengths in both Shanghai Deep Ultra-Violet Free Electron Laser （SDUV-FEL） and Shanghai X-ray Free Electron Laser （SXFEL）. Methods： In this paper, the advantages and disadvantages of three standard diagnostic tools for bunch length measurement are compared and a measuring system based on coherent transition radiation （CTR） for SDUV-FEL and SXFEL is designed and analyzed. Results： The simulation shows that the measuring system can measure the electron bunch length from 20 fs to 1 ps effectively and time resolution of the measuring system can reach 20 fs. Conclusion： Electron bunch length measurement by means of CTR is an easy way to achieve high time resolution with inexpensive experimental instruments. The measuring system meets the demands of SDUV-FEL and SXFEL well.

关 键 词：束团长度 相干渡越辐射 束流诊断 

分 类 号：TL53[核科学技术—核技术及应用]