Some reaction candidates can be eliminated at once. The D-6Li reaction has no advantage compared to p+- because it is roughly as difficult to burn but produces substantially more neutrons through - side reactions. There is also a p+- reaction, but the cross section is far too low, except possibly when "T"i > 1 MeV, but at such high temperatures an endothermic, direct neutron-producing reaction also becomes very significant. Finally there is also a p+- reaction, which is not only difficult to burn, but can be easily induced to split into two alpha particles and a neutron.