论文标题
使用结构化的光场表征超低发射器电子束
Characterizing ultra-low emittance electron beams using structured light fields
论文作者
论文摘要
过去几年已经开发了用于生成超低发射器电子束的新型方案，并承诺具有出色的光束质量的紧凑型粒子质量适合将来的高能量物理实验和自由电子激光器。当前表征低排放电子梁（例如Pepperpot测量或光束焦点扫描）的方法的能力有限，以解决低于$ 0.1 $ mm的MRAD机制。在这里，我们提出了一种新颖的，高度敏感的方法，用于使用干扰激光束对束腰部的单个射击表征和发射。在此方案中，两个激光脉冲集中在一个角度，形成类似于光向的干扰模式。当电子束与结构化激光场相互作用时，电子束的相空间被激光浮子力调节，并在进一步的电子束相位前进后导致调制梁曲线，从而可以表征超低发射光束。 2D PIC模拟显示了该技术在$ε_n= [0.01,1] $ mm MRAD范围内的归一化发射机的有效性。
Novel schemes for generating ultra-low emittance electron beams have been developed in the last years and promise compact particle sources with excellent beam quality suitable for future high-energy physics experiments and free-electron lasers. Current methods for the characterization of low emittance electron beams such as pepperpot measurements or beam focus scanning are limited in their capability to resolve emittances in the sub $0.1$ mm mrad regime. Here we propose a novel, highly sensitive method for the single shot characterization of the beam waist and emittance using interfering laser beams. In this scheme, two laser pulses are focused under an angle creating a grating-like interference pattern. When the electron beam interacts with the structured laser field, the phase space of the electron beam becomes modulated by the laser ponderomotive force and results in a modulated beam profile after further electron beam phase advance, which allows for the characterization of ultra-low emittance beams. 2D PIC simulations show the effectiveness of the technique for normalized emittances in the range of $ε_n=[0.01,1]$ mm mrad.
