The radiative-capture reaction ${}_{}{}^9{}_{}{}^{}\mathrm{Be}({}_{}{}^3{}_{}{}^{}\mathrm{He},\gamma ){}_{}{}^{12}{}_{}{}^{}\mathrm{C}$ has been studied in the bombarding energy range $1.0\le E\left({}_{}{}^3{}_{}{}^{}\mathrm{He}\right)\le 6.0$ MeV. Transitions to the ground state and first two excited states were seen. Excitation curves and angular distribution measurements indicate a broad resonance near 2.55 MeV, formed by $s$- and $d$-wave capture, suggesting the presence of a $1^{-}$, $T=1\mathrm{}$ state of ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$ at 28.2 MeV. The transitions to the two $0^{+}$ final states are strong, and show strikingly similar energy dependence. A simple interpretation of the observations in terms of a particle-hole picture of ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$ is presented.

• Received 8 June 1972

DOI:https://doi.org/10.1103/PhysRevC.6.1536