Decay ofCe144

The decay scheme of 282-day ${\mathrm{Ce}}^{144}$ was investigated using a thin-lens beta spectrometer, proportional counters, and scintillation counters. Intensity measurements and coincidence studies were used to obtain the decay scheme. Two beta rays were found; the main branch is a 76%, 309±5-kev beta ray to the ground state while the 24±5%, 175-kev beta ray goes to a 134-kev level in ${\mathrm{Pr}}^{144}$. From this level there are three parallel $\gamma$-ray branches: In 15.3% of the Ce disintegrations one observes a 134-kev gamma ray, in 7.2% a cascade of 81-kev and 54-kev gamma rays, and in 1.5% a cascade of 100 kev and 34 kev. For the conversion of the 134-kev gamma ray, ${\alpha }_K=0.71\mathrm{}\pm 0.20$ and $\frac{K}{L}=7.1\mathrm{}\pm 0.5$, while for the 81-kev gamma ray, ${\alpha }_K=1.2\mathrm{}\pm 0.3$ and $\frac{K}{L}=5.8\mathrm{}\pm 0.7$. There is insufficient intensity in the 54-kev gamma ray to explain observed coincidences and a strong unobserved 42-kev gamma ray is implied.