The differential cross section for the ${}_{}{}^{10}{}_{}{}^{}\mathrm{Be}(p, {\gamma }_0){}_{}{}^{11}{}_{}{}^{}\mathrm{B}$ reaction has been measured at 90° for $0.6\le E_p\le 6.3$ MeV. Compound resonances in ${}_{}{}^{11}{}_{}{}^{}\mathrm{B}$ have been located at (12.17±0.04)-, 12.55±0.03-, 12.91±0.02-, 14.33±0.02-, and 15.3±0.1-MeV excitation energy. The last four are probably analogs to the lowest four levels in ${}_{}{}^{11}{}_{}{}^{}\mathrm{Be}$. Total widths and ground-state $\gamma$-ray widths of these levels are presented. The spins of the 12.55- and 14.33-MeV levels are shown to be ${\frac{1}{2}}^{+}\left({\frac{3}{2}}^{+}\right)$ and ${\frac{5}{2}}^{\mathrm{}(+)\mathrm{}}\left({\frac{3}{2}}^{-}\right)$, respectively.

• Received 4 September 1969

DOI:https://doi.org/10.1103/PhysRevC.1.123