论文标题
带有升级螺旋的长行驶波管中的波粒相互作用
Wave-particle interactions in a long traveling wave tube with upgraded helix
论文作者
论文摘要
我们研究了4米长的波动波管（TWT）中电磁波和电子束的相互作用。该设备是专门设计的，可模拟束等质量实验，而没有明显的噪音。该TWT提出了升级的慢波结构（SWS），可实现更精确的测量，并使新的实验成为可能。我们引入了一个理论模型，描述了通过SWS描述波传播，并通过实验分散关系，阻抗，相位和组速度进行了验证。我们分析了梁波相互作用引起的非线性效应，例如电子束的调节以及波的生长和饱和过程。当梁电流低时，波生长系数和饱和幅度遵循线性理论预测。但是，对于高电流值，非线性空间电荷效应变得很重要，并且这些参数偏离线性预测，趋向于恒定值。饱和后，我们还观察到梁电子的捕获，从而改变了沿TWT的波幅度。
We investigate the interaction of electromagnetic waves and electron beams in a 4 meters long traveling wave tube (TWT). The device is specially designed to simulate beam-plasma experiments without appreciable noise. This TWT presents an upgraded slow wave structure (SWS) that results in more precise measurements and makes new experiments possible. We introduce a theoretical model describing wave propagation through the SWS and validated by the experimental dispersion relation, impedance, phase and group velocities. We analyze nonlinear effects arising from the beam-wave interaction, such as the modulation of the electron beam and the wave growth and saturation process. When the beam current is low, the wave growth coefficient and saturation amplitude follow the linear theory predictions. However, for high values of current, nonlinear space charge effects become important and these parameters deviate from the linear predictions, tending to a constant value. After saturation, we also observe trapping of the beam electrons, which alters the wave amplitude along the TWT.
