Cross sections for the ($\alpha$,d) reaction on ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$ and ${}_{}{}^{13}{}_{}{}^{}\mathrm{C}$ were measured at $E_{\alpha }=34.9\mathrm{}$ MeV in the range of excitation energies up to 11 MeV in ${}_{}{}^{14}{}_{}{}^{}\mathrm{N}$ and up to 13 MeV in ${}_{}{}^{15}{}_{}{}^{}\mathrm{N}$. The angular distributions were compared to calculations with the zero-range distorted-wave Born approximation with the assumption of a deuteron-cluster transfer. On the basis of the assumption that the transferred two nucleons are weakly coupled to the target nuclei, correspondences between the transferred angular momenta and the strengths for the two-nucleon pairs were found for the residual nuclei ${}_{}{}^{14}{}_{}{}^{}\mathrm{N}$ and ${}_{}{}^{15}{}_{}{}^{}\mathrm{N}$. Effects of the $0d_{\frac{3}{2}}$ shell and a necessity for the tensor force are discussed in terms of the two-nucleon configurations $d_{\frac{3}{2}}{p}_{\frac{1}{2}}$ and ${\left(d_{\frac{5}{2}}\right)}^2$, respectively.

• Received 13 March 1984

DOI:https://doi.org/10.1103/PhysRevC.30.770