Search

The /EC decay of Tl to excited states in the daughter nuclei Hg has been investigated at the CERN on-line isotope mass separator facility. In both Tl nuclei two β-decaying states were observed. In the case of 184Tl, narrow-band laser spectroscopy could be used to disentangle the decay of both isomers. In 182Hg a precise energy of 335 (1) keV for the state was measured together with its feeding from a tentatively proposed state at 973 keV. Large conversion coefficients for the transition in Hg were measured to be 7.2 (13) and 14.2 (36), respectively, evidencing a strong E0 component. [ABSTRACT FROM AUTHOR]

The neutron-deficient Pb isotopes have been studied in Coulomb-excitation experiments employing the Miniball γ-ray spectrometer and radioactive ion beams from the REX-ISOLDE post-accelerator at CERN. The reduced transition probabilities of the first excited 2+ states in 196Pb and 198Pb nuclei have been measured for the first time. Values of W.u. and W.u., were obtained, respectively. The experiment sheds light on the development of collectivity when moving from the regime governed by the generalised seniority scheme to a region, where intruding structures, associated with different deformed shapes, start to come down in energy and approach the spherical ground state. [ABSTRACT FROM AUTHOR]

Neutron-rich Ba isotopes are expected to exhibit octupolar correlations, reaching their maximum in isotopes around mass A = 146. The odd-A neutron-rich members of this isotopic chain show typical patterns related to non-axially symmetric shapes, which are however less marked compared to even-A ones, pointing to a major contribution from vibrations. In the present paper we present results from a recent study focused on 148–150Cs β-decay performed at the ISOLDE Decay Station equipped with fast-timing detectors. A detailed analysis of the measured decay half-lives and decay scheme of 149Ba is presented, giving a first insight in the structure of this neutron-rich nucleus. [ABSTRACT FROM AUTHOR]