The absolute branching ratio of the $\beta$-delayed $\gamma$-ray emission of ${}^{18}\mathrm{N}$ was measured, providing absolute normalization of the previous work by Olness et al. [Nucl. Phys. A373, 13 (1982)] who measured the relative branching ratios for the individual $\gamma$-rays. We find the total absolute branching ratio for $\beta$-delayed $\gamma$-ray emission of ${}^{18}\mathrm{N}$ to be $76.7\pm 7.2\left(\text{stat}\right)\pm 5.8\left(\text{norm}\right)\%$. A combination of other results suggests a value consistent with our result, but smaller than that calculated by Millener as quoted in Olness et al.

• Received 26 June 2003

DOI:https://doi.org/10.1103/PhysRevC.68.057302