Lumpkin A H, Dejus R, Lewellen J W, Berg W, Biedron S, Borland M, Chae Y C, Erdmann M, Huang Z, Kim K-J, Li Y, Milton S V, Moog E, Rule D W, Sajaev V, Yang B X
Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439, USA.
Phys Rev Lett. 2002 Jun 10;88(23):234801. doi: 10.1103/PhysRevLett.88.234801. Epub 2002 May 23.
We report the first measurements of z-dependent coherent optical transition radiation (COTR) due to electron-beam microbunching at high gains ( >10(4)) including saturation of a self-amplified spontaneous emission free-electron laser (FEL). In these experiments the fundamental wavelength was near 530 nm, and the COTR spectra exhibit the transition from simple spectra to complex spectra ( 5% spectral width) after saturation. The COTR intensity growth and angular distribution data are reported as well as the evidence for transverse spectral dependencies and an "effective" core of the beam being involved in microbunching.
我们报告了关于高增益（>10⁴）下电子束微聚束引起的与z相关的相干光跃迁辐射（COTR）的首次测量结果，其中包括自放大自发辐射自由电子激光（FEL）的饱和情况。在这些实验中，基波波长接近530 nm，并且COTR光谱在饱和后呈现出从简单光谱到复杂光谱（5%光谱宽度）的转变。还报告了COTR强度增长和角分布数据，以及横向光谱依赖性的证据和参与微聚束的光束“有效”核心的证据。
