用理论和粒子模拟相结合的方法分析了强流薄环形相对论电子束在低磁场导引下,在均匀波导,无箔二极管,以及锥形波导和渐减磁场位形条件下的传输过程,研究了束包络的波动和如何减少波动的问题.分析表明:在无箔二极管中一个适当渐增的磁场位形可以有效地抑制束电子的径向运动,从而减少电子在波导中的波动幅度;电子束在锥形波导和渐减磁场位形中运动,不会增加束电子的波动.因此适当的磁场位形可以降低微波器件对导引磁场的要求,有利于实现永磁包装微波器件。

Theoretical and particle simulation methods are used to investigate the transportation processes of intense relativistic electron beam(IREBs) guided by low magnetic field. It is shown that in the foilless diode, a magnetic field of tapered profile along the A-K gap can restrain the radial movement of electrons, and the undulation of radial movement is decreased in waveguide. Electrons movement guided by the magnetic field decreasing gradually along the tapered waveguide are also studied, it is found that the radial undulation of electrons is not enlarged, though the magnetic field decrease along the waveguide. A proper profile can reduce the requirement of the guiding magnetic field, it is advantageous to realize the high power microwave devices packed by permanent magnet.