Measurements of activation cross-sections of (n, n′) reaction with d-D neutrons in the energy range of 2.1-3.1 MeV

摘要

Activation cross-sections for the (n, n′) reaction were measured by means of the activation method in the energy range of 2.1-3.1 MeV employing the d-D neutron source of the Fusion Neutronics Source at the Japan Atomic Energy Research Institute. The irradiated target isotopes were ~(77)Se, ~(79)Br, ~(87)Sr, ~(89)Y, ~(107,109)Ag, ~(111)Cd, ~(113)In, ~(117)Sn, ~(137)Ba, ~(179,180)Hf, and ~(197)Au. All cross-section values were determined relative to those of the ~(115)In (n, n′) ~(115m)In reaction. In order to obtain reliable activation cross-sections, careful attention was paid to neutron irradiation and to the measurement of induced activity as well as to determining the mean neutron energy at the irradiation positions. To measure weak activity, a highly efficient measuring technique using a well-type High Purity Germanium detector was applied. The present results were compared against the comprehensive evaluated data listed in JENDL-Activation File 96 (-AF96) and FENDL/A-2.0. The evaluated data for ~(180)Hf in JENDL-AF96 and those for ~(87)Sr, ~(107)Ag, ~(113)In, ~(117)Sn and ~(137)Ba in FENDL/A-2.0 were found to be overestimated or underestimated by more than 30%.