Neutron Radiative Capture Cross Section of 232Th in the Energy Range from 0.06 to 2 MeV

The neutron capture cross section of 232Th has been measured relative to (sigma)(n, (gamma)) for 197Au and (sigma)(n,f) for 235U in the energy range from 60 keV to 2 MeV. Neutrons were produced by the 7Li (p,n) and T(p,n) reactions at the 4-MV Van de Graaff Accelerator of CEN Bordeaux-Gradignan. The activation technique was used, and the cross section was measured relative to the 197Au(n,(gamma)) standard cross section up to 1 MeV. The characteristic gamma lines of the product nuclei 233Pa and 198Au were measured with a 40% high-purity germanium detector. Above this energy, the reaction 235U(n,f) was also used as a second standard, and the fission fragments were detected with a photovoltaic cell. The results, after applying the appropriate corrections, indicate that the cross sections are close to the JENDL3 database values up to 800 keV and over 1.4 MeV. For energies in the intermediate range, our values are slightly lower than those from all the libraries.