Nonstationary processes in an X-band relativistic gyrotron with delayed feedback

This paper describes experimental and theoretical studies of nonstationary processes in a relativistic X-band gyrotron with delayed feedback. For the first time, the chaotic self-modulation regimes were realized with the power level exceeding 2 MW and efficiency up to 17%. The full particle-in-cell simulations of the self-modulation regimes have been carried out. The period-doubling pattern of the transition from the periodic to chaotic self-modulation regimes have been observed both in experiment and simulations.