Title: Two-energy-component toroidal fusion devices

Injection of a superthermal ion component into a toroidal plasma can raise the fusion power density to levels considerably higher than those attainable in ordinary one-component plasmas. As a result, energy break-even in D-T can be attained in bulk plasmas with ntau-values as low as 10$sup 13$ cm$sup - 3$.s, at temperatures of approximately 5 keV. The optimal energy of the superthermal ion component is in the range 100 to 200 keV; injection-energy requirements can be reduced by adiabatic compression prior to or during the reaction phase. The appropriate ratio anti GAMMA of fast-ion pressure to bulk- plasma pressure ismore » about 0.5. The stability of two-component tokamak plasmas was examined, and is found to be favorable for parameters of practical interest. (auth)« less