Computer investigation of coaxial gyro-bwo efficiency depending on oscillation frequency and longitudinal waveguide dimensions

In this article (first part of one) we investigated efficiency dependence of gyro-BWO on oscillation frequencies f=7.7...10 GHz under fixed injection energy of an electron beam _γ0=2. We obtained efficiency increasing of gyro-BWO from ∼10 up to ∼30% at above mentioned oscillation frequency band f=7.7...10 GHz. Then (second part) we investigated efficiency dependence on longitudinal and transversal waveguide dimensions under the same oscillation frequencies and fixed energy injection of an electron beam. High efficiency η ∼ 0.3 still remains the same under fixed distance between radii of coaxial waveguide. High efficiency η takes place too under varying length L of space interaction 60 cm ≥ L ≥ 30 cm due to form changing like-a-bell guiding magnetic field