To the electrodynamics of the hybrid plasma-waveguide structures (theory and experiment)

The plasma filled slow-wave structures (hybrid structures) have been considered and their advantages for the generation of electromagnetic radiation and for particles acceleration have been shown in comparison with vacuum structures. Dispersion characteristics, field topography and microwave power flux distribution in a chain of inductively connected cavities with plasma filled beam channel have been investigated. The generation and amplification regimes were considered. The gain, start current, thresholds of bifurcation and efficiency were estimated. The electrodynamic characteristics have been experimentally investigated for the slow-wave structures of a ring-meander type and a chain of cylindrical cavities with plasma filling. The generators were created on this base in S-band with an efficiency about 50% and high output power of 40 kW in continuous operation and 100 kW in pulse of 4 ms duration. It has been elaborated and created the power beam-plasma generator of stochastic oscillations in decimeter range using helix-plasma systems. The efficiency was 38% and output power reached 70 kW in pulse of 400 µs duration.