Evidence for octupole collectivity in $$^{172}{\mathrm {Pt}}$$172Pt

Combined in-beam electron and gamma-ray spectroscopy of 184,186Hg\u2028

By exploiting the SAGE spectrometer a simultaneous measurement of conversion electrons and gamma rays emitted in the de-excitation of excited levels in the neutron-deficient nuclei (184,186)Hg was performed. The light Hg isotopes under investigation were produced using the 4n channels of the fusion-evaporation reactions of (40)Ar and (148,150)Sm. The measured K- and L-conversion electron ratios confirmed the stretched E2 nature of several transitions of the yrast bands in (184,186)Hg. Additional information on the E0 component of the 2(2)(+) -> 2(1)(+) transition in (186)Hg was obtained.

In-beam study of No-253 using the SAGE spectrometer

Evolving collective structures in the transitional nuclei 162W and 164W

Excited states in the neutron-deficient nuclides 162 74 W88 and 164 74 W90 were investigated by using the γ -ray spectrometer Jurogam. A change in structure is apparent from the first rotational alignments in 162W and 164W, whose rotationally aligned bands are interpreted as ν(h9/2) 2 and ν(i13/2) 2 configurations, respectively. The level schemes have been extended using recoil (-decay) correlations with the observation of excited collective structures. Configuration assignments have been made on the basis of comparisons of the deduced aligned angular momentum, as a function of rotational frequency, with the predictions of the cranked shell model. peerReviewed

Single-particle and collective excitations in the transitional nucleus 166Os

The mean lifetimes of the lowest energy 2+, 8+ and 9− states in 166Os have been measured using the recoil distance Doppler-shift method in conjunction with a selective recoil-decay tagging technique. These measurements extend studies into the most neutron-deficient mass region accessible to current experimental methods. The B(E2; 2+ → 0+) = 7(2) W.u. extracted from these measurements is markedly lower than those observed in the heavier even-mass Os isotopes. The 8+ and 9− states yield reduced transition probabilities that are consistent with single-particle transitions. While these values may indicate a departure from collective structure, the level scheme and the underlying nuclear configu…

Reinvestigation of the excited states in the proton emitter Lu-151: Particle-hole excitations across the N = Z=64 subshell