Second harmonic gyro-peniotron oscillator experiment

Summary form only given, as follows. The approach under study at NRL for efficient millimeter wave operation at reduced values of the magnetic field is based on the harmonic gyro-peniotron interaction occurring in slotted waveguide structure with a high quality axis encircling beam. An efficient second harmonic TE/sub 21/ gyro-peniotron oscillator with a rising-sun slotted waveguide structure has been designed utilizing an axis-encircling beam (70 kV and 3 A). The hybrid particle-in-cell code predicts an efficiency of 60% at electron beam velocity ratio of 1.4 with cold beam. The simulated performance was optimized where B/B/sub grazing/=1.015, the quality factor of 600, and cavity length of 2 cm. Experiments are underway to demonstrate the high efficient gyro-peniotron interaction and correlation with the quality of the electron beam.