Studies on Cyclotron Higher Harmonic Auto-resonant Peniotron

回旋加速器和回旋加速器是产生高功率微波和毫米波的回旋快波管。回旋加速器在高次谐波和回旋基波下的能量转换效率高于回旋加速器。在自共振条件下工作的质子加速器能够将电子束能量完全转换为电磁波，即理论上效率达到100%。采用22片磁控管型波导谐振腔，设计并构建了第10回旋加速器谐波自谐振振荡器。谐振腔中π模式的电磁场分布与圆柱波导中TE_<11,1>模式的电磁场分布相似，可以在不使用超导磁体的情况下，在10次回旋谐波下实现质子加速器相互作用，并在100GHz下工作。仿真结果表明，该电子管在10次谐波处的效率高达40%。实验电子管在谐振腔的π模式下，通过中子相互作用产生频率在100GHz范围内的电磁波。此外，在103 ~ 110ghz频率范围内，还观察到9、11、12、13次回旋加速器谐波振荡。在磁控管型谐振器中，除10次谐波振荡外，其余振荡都是由方位旋转电磁波各自轴向模式下的质子加速器相互作用产生的。

Peniotron and gyrotron are cyclotron fast wave tubes which produce high power microwave and millimeter electromagnetic wave. Energy conversion efficiency of peniotron is higher at higher cyclotron harmonics as well as at a cyclotron fundamental than that of gyrotron. Peniotron operating at the auto-resonant condition is capable to convert completely an electron beam energy to an electromagnetic wave, that is, the efficiency reaches theoretically 100%.We designed and constructed a 10th cyclotron harmonic auto-resonant peniotron oscillator using a magnetron type waveguide resonator with 22 vanes. The electromagnetic field distribution on pi mode in the resonator is similar to that of TE_<11,1> mode in a cylindrical waveguide, which enable peniotron interaction at 10th cyclotron harmonic and operation at 100GHz without using a super conducting magnet. The simulation result of the tube showed a high efficiency of 40% at the 10th harmonic.The experimental tube generated electromagnetic waves in the frequency range of 100GHz at pi mode of the resonator by peniotron interaction.In addition, 9, 11, 12 and 13th cyclotron harmonic oscillations were observed in the tube at the frequencies of 103-110GHz. All of the oscillations except at 10th harmonic were confirmed first to be generated by peniotron interaction at respective axial modes of azimuthally rotating electromagnetic wave in the magnetron type resonator.