抄録
A hybrid Bragg resonator with an advanced and a traditional Bragg reflectors was designed to develop the frequency selectivity of the free electron maser with frequency of 40 GHz using an intense relativistic electron beam. A normal Bragg resonator with two traditional Bragg reflectors was also designed for the same frequency. The interaction between a propagating wave and a quasi-cutoff mode in an advanced Bragg reflector was expected to provide higher frequency selectivity than a traditional Bragg reflector. In the cold test, the frequency resolution of the hybrid Bragg resonator was appeared to be ±0.05 GHz, while that of the normal one was ±0.5 GHz.
