MAGIC3D Simulation of an Ultra-Compact, Highly Efficient, and High-Power Reltron Tube

In this paper, we use a three dimensional particle-in-cell (PIC) code, MAGIC3D, to investigate the operating characteristics of an ultra-compact, high power reltron tube with self-modulation beam and post-acceleration of modulated beam. The simulation model is a full 3-D model because the reltron is intrinsically a three-dimensional problem due to the asymmetrical geometry of the modulating cavity. In the reltron, the mode of operation is π/2-mode, providing the means to modulate an electron beam in short distances. Simulations show that ultra-compact reltron with a beam voltage of 120 kV and an acceleration voltage of 800 kV generates 38.3 MW high power microwave at 2.887 GHz with an electronic efficiency of 52.7%.