Simultaneous Measurements of the Neutron Fission and Capture Cross Sections for Uranium-235 for Neutron Energies from 8 eV to 10 keV

Simultaneous measurements of the neutron fission and capture cross sections of ²³⁵U have been performed at the Oak Ridge Electron Linear Accelerator for neutrons with energies between 8 eV and 10 keV. These cross sections were measured relative to the shape of the standard ¹⁰B(n,α) reaction cross section, and normalized to the Oak Ridge National Laboratory-Rensselaer Polytechnic Institute data between 100 and 200 eV. The comparison of the present ²³⁵U capture cross section with the values from other available sources shows that below 200 eV there is general agreement within an error band of ±5%. In the keV energy region, the average difference observed rises to ±12%. The fission cross-section results presented here agree with a worldwide compilation of fission data typically within a 3% error in the entire range of neutron energies investigated in this work. The values of alpha, capture-to-fission ratio, exhibit a remarkable amount of structure.