A Novel A10 Relativistic Diffraction Output High-Power Magnetron Operating at 9.8 GHz

An A10 relativistic magnetron with a diffraction output (MDO), similar to an A8 MDO operating at ~8.8 GHz investigated in recent publications, is studied using 3-D particle in cell (3-D PIC) simulations. This MDO operates at ~9.8 GHz, closer to the frequency of interest, and reaches high power and high efficiency. At high magnetic field values, considerably above the Hull limit, its amplitude consists of slow (relative to the operating frequency) power modulations with amplitudes reaching twice that of the corresponding input power with no evident mode competition and without violating energy conservation. This feature has been revealed for the A8 magnetron and explained by the dynamics of the longitudinal motion of the excess electron charge oscillating in the potential well bounded by two conducting reflectors (cathode endcaps). This mechanism is also supported by the present results.