β − Decay of 150 Ce to Odd–Odd 150 Pr

The β− decay of 150Ce having a half-life of 6.05(7) s produced by the thermal-neutron-induced fission of 235U has been studied using the on-line isotope separator at the Kyoto University Research Reactor. A decay scheme containing 18 excited levels and 55 γ-rays was constructed from γ-ray singles and γ–γ coincidence measurements. Of these, 9 levels and 37 γ-rays were newly placed. The dominant β-feeding observed at the 110 keV level of 150Pr was found to be an allowed unhindered spin-flip transition. On the basis of the systematics of the neighboring nuclides, the Gallagher–Moszkowski coupling rules, and the selection rules for the β-decay of deformed nuclei, the Nilsson configurations of the ground and 110 keV states in 150Pr were newly proposed to be π5/2+[413]–ν3/2−[521] and π5/2−[532]–ν3/2−[532], respectively.