ABSTRACT
Neutron diffusion theory is the backbone of a nuclear reactor. It gives scientific insights to study various nuclear design problems. The neutrons are characterized by a single energy or speed in one-group diffusion theory and the model allows preliminary design estimates (Keepen 1964). Multigroup diffusion and transport theory may also be analyzed by assuming the same mathematical models used for primary design estimates. Here, the scattering of neutron depends on the cross section of neutron reactions, rates of neutron reactions, fission neutrons, prompt neutrons and delayed neutrons.
