Angular distributions have been measured at 50 MeV for the ${}_{}{}^9{}_{}{}^{}\mathrm{Be}({\pi }^{+}, p){}_{}{}^8{}_{}{}^{}\mathrm{Be}$ reaction leading to the $0^{+}$, $2^{+}$, and $4^{+}$ states of ${}_{}{}^8{}_{}{}^{}\mathrm{Be}$. An angular momentum selection rule is considered in order to account for the preferential excitation of high spin states. Two-step processes in the framework of the distorted-wave Born approximation and momentum sharing in the two-nucleon model are also discussed.

NUCLEAR REACTIONS ${}_{}{}^9{}_{}{}^{}\mathrm{Be}({\pi }^{+}, p){}_{}{}^8{}_{}{}^{}\mathrm{Be}$, $E_{\pi }=50\mathrm{}$ MeV; measured $\sigma \left(\theta \right)$; reaction mechanism discussed.

• Received 22 April 1980

DOI:https://doi.org/10.1103/PhysRevC.22.2531