Safety Based on Reflector Neutrons

Ordinarily, reactors are characterized by safety based on delayed and prompt neutrons. In the present communication,we proposed safety based on the neutrons of a reflector made of material with low absorption and high atomic number.Methods of evaluating the average lifetime of the neutrons of a reflector in a fast reactor with respect to a fission chain reaction are studied. The safety of a fast reactor can be increased by surrounding the core with a reflector with low neutron absorption and large atomic mass. A suitable material is lead enriched with 208Pb. The neutrons leaving the core will return to it with a significant delay, which actually signifies an increase of the lifetime of prompt neutrons with the fast reactor spectrum being preserved.