Theoretical estimate of the fast-neutron fission cross sections of235,238U

The cross sections for fissioning of {sup 235,238}U by fast neutrons have been studied experimentally in greater detail and with higher accuracy than the same cross sections for other actinide nuclei. As a result, they are used as neutron standards in the range of neutron energies E{sub n} from several hundreds of keV up to 20 MeV. They are widely employed in relative measurements of other cross sections, primarily the fission cross sections of less-studied nuclei. This methodological solution considerably expanded the possibilities for performing systematic investigations of {sigma}{sub f}(E{sub n}, Z, A) for many nuclei that play an appreciable role in nuclear technology. However, the requirements of nuclear technology cannot be solved by measurements alone, especially in the case of highly active short-lived target nuclei. Attempts are being made to eliminate the associated deficiencies and problems in the experimental information by means of theoretical calculations.