Measurement and covariance analysis of 232 Th(n, 2n) 231 Th reaction cross sections at the effective neutron energies of 8.97 and 16.52 MeV

The \({}_{ }^{ 2 3 2} {\text{Th(n, 2n)}}{}_{ }^{ 2 3 1} {\text{Th}}\) reaction cross sections relative to the \({}_{ }^{ 2 3 2} {\text{Th}}\)(n, f)97Zr monitor reaction at the effective neutron energies of 8.97 and 16.52 MeV have been measured by using the activation and off-line \(\gamma\)-ray spectrometry. The neutron beams were generated from the \({}_{ }^{7} {\text{Li}}\left( {{\text{p}}, {\text{n}}} \right){}_{ }^{7} {\text{Be}}\) reaction by using the proton beam energies of 11 and 18.8 MeV. Correction factors for the low energy neutrons were taken care by considering the thickness of sample and non mono-energetic neutrons. The covariance analysis in the uncertainty of the reaction cross section was carried out by using error propagation and micro-correlation technique. The present data were compared with the literature data, evaluated data and theoretical values based on TALYS-1.8 code.