Glen Hickey

The polarization of neutrons elastically scattered from ¹⁶0 at nine angles ranging from 20° to 160° has been measured as a continuous function of energy between 1 and 4 MeV using a neutron double-scattering technique. The neutron energies were determined using the nanosecond neutron time-of­ flight spectrometer associated with the Yale University Electron Linear Accelerator. The primary intense flux of unpolarized neutrons was generated by the photo-disintegration of natural lead and uranium. A fraction of these neutrons was elastically scattered from a graphite cylinder and emerged in a state of known polarization. The polarized beam was then scattered from a liquid oxygen target placed at an angle of 130° with respect to the graphite scatterer. The measured polarizations were analyzed using a general, multi­-level R-matrix reaction theory. A self-consistent set of resonance parameters were derived which were then used to predict the neutron differential and total cross sections from Ovto 4 MeV. These predictions are found to be in good agreement with published work. However, a comparison between the present results and recent theoretical calculations indicates the need for improvements in both the nuclear structure and nuclear reaction aspects of the theory.