The effects of the phase variation, the evolution of the electron beam, the evolution of the radiation intensity, and the higher-order modes due to waveguides on a free-electron laser (FEL) oscillator have been analyzed by using two electron beams of different energies based on the proposed FEL facility which is to be operated in the far-infrared and infrared regions. The three-dimensional (3D) effects on a FEL oscillator due to waveguides and higher-order modes were studied using an extended 3D FEL code with two electron beams that we have developed. The effects of the variation on the amplitude of radiation on the electron beam's emittance and energy spreads were also calculated in the case of waveguide for multi-particle and multi-pass numbers by using a new 3D code. The phase variation, the variation in the beam envelope, the evolution of the amplitude, and power were calculated for the fundamental mode. The results were compared with those of the higher-order modes of the wiggler for various TE and TM modes for determining the FEL's performance which is required for high-quality electron beams.

中文翻译：

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波导对具有两束电子束的自由电子激光器的影响

通过使用两个不同的电子束，分析了相位变化、电子束演化、辐射强度演化以及自由电子激光器 (FEL) 振荡器上波导引起的高阶模式的影响。基于拟议的 FEL 设施的能量，该设施将在远红外和红外区域运行。使用我们开发的带有两个电子束的扩展 3D FEL 代码研究了由于波导和高阶模式对 FEL 振荡器的三维 (3D) 效应。还使用新的 3D 代码计算了在多粒子和多通道数波导的情况下，辐射幅度变化对电子束发射率和能量扩散的影响。相位变化，光束包络的变化，计算了基模的振幅和功率的演变。将结果与各种 TE 和 TM 模式的摆动器的高阶模式的结果进行比较，以确定高质量电子束所需的 FEL 性能。