MEASUREMENT OF ACTIVATION CROSS-SECTIONS ON TANTALUM AND TUNGSTEN WITH 14-MEV NEUTRONS

The cross sections of Ta-181(n, p)Hf-181, Ta-181(n, n'p)Hf-180m, W-184 (n, alpha)Hf-181, W-186(n, n'p)Ta-185 and W-186(n, alpha)Hf-183 reacti ons have been measured in the energy range between 13.4 and 14.9 MeV b y the activation method. The intense 14 MeV neutron source facility (O KTAVIAN) at Osaka University was used for irradiation. The gamma-rays emitted from the irradiated samples were measured with high-purity ger manium (HPGe) detectors. All cross section values were obtained relati ve to the standard reaction cross section of Nb-93(n, 2n)Nb-92m obtain ed by Netha way. The cross sections of Ta-181(n, n'p)Hf-180m reaction were measured for the first time. The present results were compared wi th previous data and the evaluated data of JENDL-3 and ENDF/B-VI, and the comparison showed that some significant discrepancies exist.