Proton-Neutron Final-State Interactions in theD(d, dp)nReaction

The reaction $\mathrm{D}(d, dp)n$ has been studied at bombarding energies between 11 and 13 MeV. Two charged particles were detected in coincidence at pairs of angles corresponding to the recoil axes of the reaction $\mathrm{D}(d, d)d^{*}$ where $d^{*}$ is a $p-n$ system at zero relative energy. Time-of-flight and $\Delta E-E$ information were used for background subtraction and particle identification, respectively. The experimental spectra are dominated by strong peaks at low relative energies in the $p-n$ system which are in part attributable to the isospin-forbidden formation of the "singlet deuteron." The shape of the experimental spectra is not predicted very well by either Watson-Migdal or Phillips, Griffy, Biedenharn theories.