Measurement of neutron inelastic scattering cross-section for the first level of 238U in hundreds of keV range

Neutron inelastic scattering cross-section for the first level of 238U (Ex=44.9 keV) was measured for eight incident energy points from 350 to 855 keV at laboratory angle of 120 deg. by using a time-of-flight spectrometer. Care was taken for the peak separation of the first level from the ground state, and for the absolute normalization of the cross-section. The peak separation was achieved by employing a thin neutron production target (ΔE≤10 keV), a long flight path (4-6 m), and by experimental simulation of the elastic scattering peak with a lead sample. Validity of the absolute value and internal consistency in the experiment were confirmed by measuring carbon with well-known cross-sections and 238U at another emission angle, 135 deg. The angle-integration was performed by employing the angular distribution of JENDL-3.2. The present experimental data for the first level and the ground state are close to the JENDL-3.2 data