The Feasibility Of Fusion Reactors Fueled With D-3He And D-D.

In this paper we discuss the feasibility of fusion reactors based on D-(3)He and D-D fuel mixtures. The low reactivity of the D-(3)He and D-D fusion reactions and the large energy losses due to bremsstrahlung and synchrotron radiation at high plasma temperatures severely restricts the choice of fuel mixtures that can be brought to ignition. These fuel mixtures are extremely sensitive to impurities and to helium ash retention and they would require reactor conditions (plasma density, temperature, beta and energy confinement time) that are much more demanding than the requirements for D-T. A reactor burning D-(3)He or D-D would be far beyond the most optimistic extrapolations of known magnetic confinement schemes, it would have problems with sustainable fuel supplies and it would produce substantial numbers of neutrons. Our conclusion is that these fuels cannot be considered as realistic alternatives to D-T.