Experimental apparatus at KUR-ISOL to identify isomeric transitions from fission products, and decay spectroscopy of 151Ce

Decay studies on 151Ce have been performed using the on-line isotope separator connected to the Kyoto University Reactor. In addition to conventional γ and conversion electron spectroscopy, β -gated measurements were carried out on mass-separated 151Ce to identify an isomeric transition. From the analysis of the obtained data, the half-life of the isotope was ascertained to be 1.76(6) s and a decay scheme containing six excited levels was constructed for the first time. The excited level at 35.1 keV in 151Pr was found to be a long-lived state (a half-life of approximately 10 μ s or longer).