A new method to generate relativistic comb bunches with tunable subpicosecond spacing  

作　　者：DU Ying-Chao HUANG Wen-Hui TANG Chuan-Xiang 杜应超;黄文会;唐传祥(Accelerator Laboratory,Department of Engineering Physics,Tsinghua University,Beijing 100084,China;Key Laboratory of Particle and Radiation Imaging(Tsinghua University),Ministry of Education,Beijing 100084,China;Key Laboratory of High Energy Radiation Imaging Fundamental Science for National Defense,Beijing 100084,China)

机构地区：[1]Accelerator Laboratory,Department of Engineering Physics,Tsinghua University,Beijing 100084,China [2]Key Laboratory of Particle and Radiation Imaging(Tsinghua University),Ministry of Education,Beijing 100084,China [3]Key Laboratory of High Energy Radiation Imaging Fundamental Science for National Defense,Beijing 100084,China

出　　处：《Chinese Physics C》2012年第2期151-155,共5页中国物理C（英文版）

基　　金：Supported by National Natural Science Foundation of China (NSFC) (10735050, 10805031);National Basic Research Program of China (973 Program) (2007CB815102)

摘　　要：We propose and analyze a scheme to produce comb bunches, i.e. a bunch consisting of micro-bunch trains, with tunable subpicosecond spacing. In the scheme, the electron beam is first deflected by a deflecting cavity which introduces a longitudinal-dependent linear transverse kick to the particles. After passing through a drift space, the transverse beam size is linearly coupled to the longitudinal position of the particle inside the beam, and a mask is placed there to tailor the beam, then the mask distribution is imprinted on the beam＇s longitudinal distribution. A quadrupole magnet and another deflecting cavity are used in the beam line to compensate the transverse angle due to the first deflecting cavity. Analysis shows that the number, length, and spacing of the trains can be controlled through the parameters of the deflecting cavity and the mask. Such electron bunch trains can be applied to an infrared free electron laser, a plasma-wakefield accelerator and a supper-radiance THz source.We propose and analyze a scheme to produce comb bunches, i.e. a bunch consisting of micro-bunch trains, with tunable subpicosecond spacing. In the scheme, the electron beam is first deflected by a deflecting cavity which introduces a longitudinal-dependent linear transverse kick to the particles. After passing through a drift space, the transverse beam size is linearly coupled to the longitudinal position of the particle inside the beam, and a mask is placed there to tailor the beam, then the mask distribution is imprinted on the beam＇s longitudinal distribution. A quadrupole magnet and another deflecting cavity are used in the beam line to compensate the transverse angle due to the first deflecting cavity. Analysis shows that the number, length, and spacing of the trains can be controlled through the parameters of the deflecting cavity and the mask. Such electron bunch trains can be applied to an infrared free electron laser, a plasma-wakefield accelerator and a supper-radiance THz source.

关 键 词：bunch trains mask deflecting cavity 

分 类 号：TL501.5[核科学技术—核技术及应用]