Levels of ${}_{}{}^{141}{}_{}{}^{}\mathrm{Cs}$ and ${}_{}{}^{141}{}_{}{}^{}\mathrm{Ba}$ from the decays of ${}_{}{}^{141}{}_{}{}^{}\mathrm{Xe}$ and ${}_{}{}^{141}{}_{}{}^{}\mathrm{Cs}$

The $\gamma$ rays and conversion electrons following the $\beta$ decay of ${}_{}{}^{141}{}_{}{}^{}\mathrm{Xe}$ and ${}_{}{}^{141}{}_{}{}^{}\mathrm{Cs}$ have been measured by applying on-line mass-separation techniques to ${}_{}{}^{235}{}_{}{}^{}\mathrm{U}$ fission products. Internal-conversion coefficients were determined for 10 transitions, and level schemes for the two daughter nuclei, ${}_{}{}^{141}{}_{}{}^{}\mathrm{Cs}$ and ${}_{}{}^{141}{}_{}{}^{}\mathrm{Ba}$, are proposed based on the study of $\gamma$-singles, $\gamma \gamma$-coincidence, and internal-conversion electron spectra.

RADIOACTIVITY ${}_{}{}^{141}{}_{}{}^{}\mathrm{Xe}$, ${}_{}{}^{141}{}_{}{}^{}\mathrm{Cs}$; measured $E_{\gamma }$, $I_{\gamma }$, $\gamma \gamma$ coin, ICC; deduced $log\mathrm{ft}$; measured $T_{\frac{1}{2}}$ ${}_{}{}^{141}{}_{}{}^{}\mathrm{Xe}$, ${}_{}{}^{141}{}_{}{}^{}\mathrm{Cs}$; deduced levels. On-line measurements, mass-separated ${}_{}{}^{235}{}_{}{}^{}\mathrm{U}$ fission products.