Advanced Quasi Optical Launcher Systems

78620S Recently completed electromagnetic analysis and synthesis codes have been used to generate the most efficient designs for Vlasov-Denisov type quasi-optical (QO) launchers in gyrotrons. However, there remain significant improvements that can be achieved over the existing QO launcher and mirror transmission approaches. Examples of advanced QO launcher concepts include compact QO launchers, coaxial mode QO launchers, step-tunable launchers and systems for direct coupling of cavity mode power to corrugated waveguide. In this project, existing codes developed for analysis and design of Vlasov-Denisov type QO launchers will be modified to increase capability and computational speed. These codes will then be used to design advanced QO launcher systems that are relevant for gyrotrons for the International Thermonuclear Experimental Reactor, the DIII-D tokamak at General Atomics, and the ASDEX tokamak in Germany. In Phase I, existing electromagnetic analysis codes developed for analysis and design of Vlasov-Denisov type QO launchers will be extended to allow analysis of advanced coupling design concepts. The code extensions will allow for analysis/synthesis of mirrors in the launcher near field, coax launchers, and step-tunable launchers. Commercial Applications and Other Benefits as described by the awardee: New designs based on the modified codes should reduce electron cyclotron heating system costs by approximately 10%, and make gyrotron systems more compact. In fusion systems, the improvements should increase the efficiency of the system and deliver more power to the tokamak plasma. Other applications include the stabilization of neoclassical tearing modes, plasma diagnostics, and spectroscopy, including electron paramagnetic resonance spectroscopy.