Reaction<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mi mathvariant="normal">D</mml:mi><mml:mn/><mml:mo>(</mml:mo><mml:mi>d</mml:mi><mml:mo>,</mml:mo><mml:mi>n</mml:mi><mml:mo>)</mml:mo><mml:mn/><mml:mrow><mml:mmultiscripts><mml:mrow><mml:mi mathvariant="normal">He</mml:mi></mml:mrow><mml:mprescripts/><mml:mrow/><mml:mrow><mml:mn>3</mml:mn></mml:mrow><mml:mrow/><mml:mrow/></mml:mmultiscripts></mml:mrow></mml:math>at 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 $\mathrm{D}(d,n)^{3}\mathrm{He}$ at 0\ifmmode^\circ\else\textdegree\fi{} with the incoming beam polarized to the extent ${p}_{3}={p}_{33}\ensuremath{\approx}0.82$ 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 ${E}_{n}=10$ MeV this process is outstanding.