Elastic Scattering of 3.1-Mev Polarized Neutrons

By using a partially polarized neutron beam from the $\mathrm{D}(d, n){\mathrm{He}}^3$ reaction, the elastic scattering polarization of a number of elements has been observed. For Be and C scatterers, the angular dependence of the polarization can be correlated with parameters characterizing compound-nucleus levels excited by the incident neutrons. For medium and heavy scattering nuclei, the observed polarization is in poor agreement with the few existing optical-model calculations for 3.1-Mev neutrons. With the exception of Pb, all medium and heavy elements studied yielded positive polarization in the 30°-60° range of scattering angles, i.e., they would produce polarization in the direction ${\mathrm{k}}_n\times {{\mathrm{k}}_n}^{\prime }$ in single scattering events.