Cross-sections of neutron induced reaction in intermediate and heavy nuclei

Interaction of neutrons with the nuclides in the Mev energy range gives rise to binary and tertiary reactions. The various induced reactions are (n,n'), (n,2n), (n,3n), (n,p), (n,d), (n,t), (n,He3), (n,α), (n,np), (n,nd), (n,nt), (n,nHe3), (n,nα), (n,pn), (n,2p), (n,αn), (n,αp), (n,dn) and (n,pα). The cross-sections of these reactions can be predicted with the statistical theory. In the structural elements used in nuclear reactors (n,p), (n,np), (n,pn), (n,2p), (n,α), (n,nα) and (n,αn) reactions are significant since they lead to the production of hydrogen and helium gases which cause swelling in rhem when they are exposed to high neutron fluences. The cross-sections of all these reactions have been evaluated in the energy range 0.5 Mev to 20 Mev for V51, Cr50, Cr52, Cr53, Cr54, Fe54, Fe56, Fe60, Ni58, Ni60, Nb93, and Nb94. It is mentioned that by using the statistical empirical model, it is possible to predict cross-sections which have not been measured. (author)