The gas-filled recoil separator RITU, combined with Ge detector arrays at the Department of Physics, University of Jyväskylä (JYFL), Finland, has successfully been employed in recoil-decay-tagging (RDT) experiments for probing structures of several very neutron-deficient heavy nuclei for the first time. In this paper new data for Hg, Pb and Po nuclei are summarized and discussed. These data shed new light on the behaviour and role of the proton multiparticle-multihole intruder states in nuclei at the 82

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The neutron-deficient mercury isotopes serve as a classical example of shape coexistence, whereby at low energy near-degenerate nuclear states characterized by different shapes appear. The electromagnetic structure of even-mass 182-188 Hg isotopes was studied using safe-energy Coulomb excitation of neutron-deficient mercury beams delivered by the REX-ISOLDE facility at CERN. The population of 0 + 1,2 , 2 + 1,2 and 4 + 1 states was observed in all nuclei under study. Reduced E2 matrix elements coupling populated yrast and non-yrast states were extracted, including their relative signs. These are a sensitive probe of shape coexistence and may be used to validate nuclear models. The experimental results are discussed in terms of mixing of two different configurations and are compared with three different model calculations: the Beyond Mean Field model, the Interacting Boson Model with configuration mixing and the General Bohr Hamiltonian. Partial agreement with experiment was observed, hinting to missing ingredients in the theoretical descriptions. a

Gamma rays from excited states feeding a proton-emitting isomeric-state in 151 Lu have been observed for the first time. Comparison with state-of-the-art nonadiabatic quasiparticle calculations indicates an oblately deformed, 3/2 + proton-emitting state with a quadrupole deformation of β 2 = −0.11. The calculations suggest an increase in quadrupole deformation, to β 2 = −0.18, with increasing spin which is understood in terms of the mixing of Nilsson states at the Fermi surface. It is also shown that the proton decay half-life is consistent with that from a 3/2 + state with a quadrupole deformation of β 2 = −0.12.