Computer Simulations of Radiation Generation From Relativis-tic Electron Beams

国际和平研究所建议使用改进的相对论电磁粒子代码以及在他们之前的国家科学基金拨款(ECS-8219105)下开发的现有代码来解决与相对论电子束产生相干辐射有关的关键问题。模拟研究将在微波范围内进行，包括自由电子激光器、电子回旋脉泽和切伦科夫脉泽。研究内容包括：交流和直流空间电荷场对各种大电流自由电子器件的增益、谐振条件和非线性效率的影响；各种自由电子器件中的横模竞争；使用背景等离子体进行束流直流空间电荷和电流中和的有效性；利用相对论电子束和填充等离子体波导之间的相互作用建立相干辐射源的可行性；以及切伦科夫脉泽在平面介质波导中的效率和使用绕轴大电子轨道的高次谐波回旋管的效率。

The PI's propose to use improved relativistic electromagnetic particle codes as well as existing codes developed under their previous NSF grant (ECS-8219105) to address crucial issues concerning the generation of coherent radiation from relativistic electron beams. The simulation studies will be carried out in the microwave range and will include the free-electron laser, electron cyclotron maser, and Cherenkov maser. The research will investigate: the effects of ac and dc space charge fields on the gain, resonant condition and nonlinear efficiency of various high current free electron devices; the transverse mode competition in various free electron devices; the effectiveness of using a background plasma for beam dc space charge and current neutralization and the feasibility of using the interaction between relativistic electron beams and plasma filled waveguides to build coherent radiation sources; and the efficiency of a Cherenkov maser in a planar dielectric waveguide and a high-harmonic gyrotron using axis-encircling large electron orbits.