ReactionD(d,n)He3at 0° with Polarized Beam: A New Source of Polarized Neutrons from 7 to 18 MeV

Experimental results are reported for the neutron polarization from the reaction $\mathrm{D}\mathrm{}(d,n)\mathrm{}{}_{}{}^3{}_{}{}^{}\mathrm{He}$ at 0° with the incoming beam polarized to the extent $p_3=p_{33}\approx 0.82$ perpendicular to the direction of motion, where $p_3$ and $p_{33}$ are components of vector and tensor polarizations, respectively. The measured neutron polarization varies in the range 0.65 to 0.72 for $E_d$ in the range 4.1 to 15.1 MeV. The measurements are consistent with a process in which the neutron spin suffers little interaction. The influence of the deuteron $D$ state is noted. Comparison is made to several other sources of polarized neutrons, with the conclusion that near $E_n=10\mathrm{}$ MeV this process is outstanding.