ACTIVATION CROSS-SECTIONS FOR GENERATION OF LONG-LIVED RADIONUCLIDES

Results of recent measurements of activation cross sections leading to the generation of long-lived radionuclides of importance in fusion re actor technology are summarized. The cross sections measured are Ag-10 9(n, 2n)Ag-108m, Eu-151(n, 2n)Eu-150m, Eu-153(n, 2n)Eu-152g, Tb-159(n, 2n)Tb-158, Hf-179(n, 2n)Hf-178m2, (193)lr(n, 2n)(192m2)lr, Bi-209(m, 2n)Bi-208, Mo-94(n, p)Nb-94, Cd-108(n, p)Ag-108m, Ba-137(n, p)Cs-137 a nd W-182(n, n' a)Hf-178m2 at 14 MeV. The neutron fluences are determin ed by the cross sections of Fe-54 (n, p)Mn-54 and Nb-93(n, 2n)Nb-92m r eactions. The neutron energies in these measurements are determined by cross section ratios for Zr-90(n, 2n)Zr89m+g and Nb-93(n, 2n)Nb-92m r eactions.(1)