CONFINEMENT OF ALPHA-PARTICLES IN LOW-ASPECT-RATIO DEUTERIUM-TRITIUM IGNITED TOKAMAKS

The effect of reducing the aspect ratio on the confinement of deuteriu m-tritium fusion products, i.e., alpha particles, in tokamaks is discu ssed. It is shown that for low-aspect-ratio tokamak reactors, the alph a-particle heating efficiency can be similar to conventional tokamaks; at the same time, the alpha-particle confinement time can be much sho rter than that of conventional tokamaks. Thus, one can facilitate alph a-particle ash removal while maintaining high alpha-particle heating e fficiency by reducing the aspect ratio.