Analysis of the ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}({}_{}{}^6{}_{}{}^{}\mathrm{Li}, \alpha ){}_{}{}^{14}{}_{}{}^{}\mathrm{N}$ reaction for $E\left({}_{}{}^6{}_{}{}^{}\mathrm{Li}\right)=33\mathrm{}$ MeV

The ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}({}_{}{}^6{}_{}{}^{}\mathrm{Li}, \alpha ){}_{}{}^{14}{}_{}{}^{}\mathrm{N}$ reaction to the first eight $T=0\mathrm{}$ states was studied at $E\left({}_{}{}^6{}_{}{}^{}\mathrm{Li}\right)=33\mathrm{}$ MeV in the angular range $12.5°\le \theta \le 165°$. The measurements for the positive parity states in ${}_{}{}^{14}{}_{}{}^{}\mathrm{N}$ also included the angular range from 2.5°-12.5°. Calculations for the angular distributions were done within the framework of the distorted-wave Born approximation (DWBA) with three different prescriptions: (1) zero-range two-particle transfer, (2) finite-range deuteron-cluster transfer, and (3) finite-range two-particle transfer, which included a full microscopic description of the two nucleon wave function. None of the three types of DWBA calculations could reproduce the data. Consequently, the possibility of multistep contributions was investigated by computing the spectroscopic amplitudes for transitions from the $2^{+}$ first excited state in ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$ to the first two states in ${}_{}{}^{14}{}_{}{}^{}\mathrm{N}$. It was found that the transfer strengths from the ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$ (4.43 MeV) to the ${}_{}{}^{14}{}_{}{}^{}\mathrm{N}$ (0.00 MeV) and ${}_{}{}^{14}{}_{}{}^{}\mathrm{N}$ (3.95 MeV) $J^{\pi }=1^{+}$ levels are larger than those from the ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$ ground state. These results coupled with previous results showing that the ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}({}_{}{}^6{}_{}{}^{}\mathrm{Li}, \alpha ){}_{}{}^{14}{}_{}{}^{}\mathrm{N}$ reaction is not compound at this energy imply that multistep mechanisms may be very important.

NUCLEAR REACTIONS ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}({}_{}{}^6{}_{}{}^{}\mathrm{Li}, \alpha )$; $E=33\mathrm{}$ MeV; measured $\sigma \left(\theta \right)$, ${\theta }_{\mathrm{lab}}=2.5\mathrm{}°-165\mathrm{}°$; compared with zero range and finite range DWBA.