Ha G, Cho M H, Namkung W, Power J G, Doran D S, Wisniewski E E, Conde M, Gai W, Liu W, Whiteford C, Gao Q, Kim K-J, Zholents A, Sun Y-E, Jing C, Piot P
POSTECH, Pohang, Gyeongbuk 37673, Republic of Korea.
Argonne National Laboratory, Argonne, Illinois 60439, USA.
Phys Rev Lett. 2017 Mar 10;118(10):104801. doi: 10.1103/PhysRevLett.118.104801. Epub 2017 Mar 9.
We report on the experimental generation of relativistic electron bunches with a tunable longitudinal bunch shape. A longitudinal bunch-shaping (LBS) beam line, consisting of a transverse mask followed by a transverse-to-longitudinal emittance exchange (EEX) beam line, is used to tailor the longitudinal bunch shape (or current profile) of the electron bunch. The mask shapes the bunch's horizontal profile, and the EEX beam line converts it to a corresponding longitudinal profile. The Argonne wakefield accelerator rf photoinjector delivers electron bunches into a LBS beam line to generate a variety of longitudinal bunch shapes. The quality of the longitudinal bunch shape is limited by various perturbations in the exchange process. We develop a simple method, based on the incident slope of the bunch, to significantly suppress the perturbations.
我们报告了具有可调纵向束团形状的相对论电子束团的实验产生情况。一条纵向束团整形（LBS）束线，由一个横向掩模和其后的横向到纵向的发射度交换（EEX）束线组成，用于定制电子束团的纵向束团形状（或电流分布）。掩模塑造束团的水平分布，而EEX束线将其转换为相应的纵向分布。阿贡尾场加速器射频光注入器将电子束团注入LBS束线以产生各种纵向束团形状。纵向束团形状的质量受到交换过程中各种扰动的限制。我们基于束团的入射斜率开发了一种简单方法，以显著抑制这些扰动。
