Breeding with uranium 233:
For breeding to take place, every gram of fissile matter burned up should be replaced by one gram or more of new fissile nuclei in the fuel. In the case of uranium 233 practically all neutron energies meet this condition. Breeders operaring with an thorium-uranium 233 fuel can sustain themselves for the whole range of neutron energy, including slow neutrons..
IN2P3