Resonance parameters and resonance integral of Thorium-232

By using the linac time-of-flight method, neutron transmission spectra through metallic thorium samples were measured with a 6Li glass scintillator, placed at the 22 m station. Area method by Hughes was firstly applied to the transmission data for the first four s-wave resonances of Th-232. Least squares shape analysis using SIOB code was employed in obtaining the neutron and capture widths for the 21 s-wave resonances. The results satisfactorily agreed with the recent measurements done by Olsen and Chrien. In order to make an integral check of the resonance parameters, the resonance integrals for the 232Th(n,γ) reaction calculated with the evaluated parameters in JENDL-2, ENDF/B-IV and -V have been compared with that measured in the 1/E spectrum field. The calculation has been also performed by exchanging the parameters in the evaluated libraries for the parameters measured above. Resonance parameters from JENDL-2 have been found to be smaller than those measured for the first four s-wave resonances. (author)