The energies and relative intensities of the $\gamma$-ray transitions connecting the bound levels of ${}_{}{}^{13}{}_{}{}^{}\mathrm{C}$ are determined. Level energies and $\gamma$-ray branching ratios are derived from these measurements. It is proposed that a mixed ${}_{}{}^{10}{}_{}{}^{}\mathrm{B}$-Pu source—emitting ${}_{}{}^{13}{}_{}{}^{}\mathrm{C}$ $\gamma$ rays of 3683.921±0.023 and 3853.170±0.022 keV—can provide a valuable $\gamma$-ray calibration standard. The measured branching ratios are combined with previous lifetime measurements to give electromagnetic matrix elements which are compared to the predictions of a large basis shell-model calculation.

NUCLEAR REACTIONS ${}_{}{}^{10}{}_{}{}^{}\mathrm{B}(\alpha , p){}_{}{}^{13}{}_{}{}^{}\mathrm{C}$, ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}(d, p){}_{}{}^{13}{}_{}{}^{}\mathrm{C}$, $E_{\alpha }=1.66\mathrm{}$ MeV, $E_d=2.51\mathrm{}$ MeV. measured $E_{\gamma }$; deduced level energies; measured branching ratios; deduced ${\mathrm{}\left|M\right(ML\left)\right|}^2$ and ${\mathrm{}\left|M\right(EL\left)\right|}^2$. Ge(Li) detectors.

• Received 15 July 1980

DOI:https://doi.org/10.1103/PhysRevC.22.2330