Recent studies on short-lived fission-product nuclei using the on-line isotope separator KUR-ISOL

The He-jet fed isotope separator on-line facility (KUR-ISOL) attached to KUR (Kyoto University Reactor) has been used for the studies of neutron-rich nuclei in the rare-earth region. Recently two isotopes, 152Ce (T1/2 = 1.4 ± 0.2 s) and 154Pr (T1/2 = 2.3 ± 0.1 s), have been newly identified. From the γ-ray energies observed following the decay of 154Pr, the excitation energy of the first excited state of 154Nd was found to be 70.8 keV which indicates that the moment of inertia of this nucleus is the largest among those of known even-even nuclei in the rare-earth region. Nuclear spectroscopic studies on several short-lived nuclei around A = 150 have been performed and a lot of new results have been obtained. Ion implanted 140Cs nuclei have been used for a solid-state physics research. Main results of these progresses will be described together with the recent developments on KUR-ISOL and on the high-efficiency, low-background detecting systems. (author)