Selective population of maximum-Jstates in thed,αreaction at 80 MeV

The ($d,\alpha$) reactions on ${}_{}{}^{40,44,48}{}_{}{}^{}\mathrm{Ca}$ and ${}_{}{}^{58}{}_{}{}^{}\mathrm{Ni}$ have been studied using the 80 MeV incident deuteron beam of the Orsay synchrocyclotron. It was found that satisfactory distorted wave Born approximation fits can be obtained. The experimental angular distributions were structured and thus provide minimal ambiguity in the determination of the angular momentum transfer. The angular momentum matching conditions greatly favored large values for the angular momentum transfer. Together with the selectivity of the ($d,\alpha$) reactions, it allowed the identification of $7^{+}$ states in ${}_{}{}^{38,42,46}{}_{}{}^{}\mathrm{K}$ and ${}_{}{}^{56}{}_{}{}^{}\mathrm{Co}$. The observation of $7^{+}$ levels in ${}_{}{}^{38,42,46}{}_{}{}^{}\mathrm{K}$ gives a measure of the $f_{\frac{7}{2}}$ proton occupation number in the ground state of the target nuclei ${}_{}{}^{40,44,48}{}_{}{}^{}\mathrm{Ca}$. An apparent enhancement of certain of the $3^{+}$ states at high excitation energy was observed in ${}_{}{}^{46}{}_{}{}^{}\mathrm{K}$ and ${}_{}{}^{56}{}_{}{}^{}\mathrm{Co}$ and the relative $3^{+}$, $7^{+}$ separation was in qualitative agreement with a simple shell-model picture.