Decay properties of the new neutron-deficient nuclide {sup 192}At have been studied in the complete fusion reaction {sup 144}Sm({sup 51}V,3n){sup 192}At at the velocity filter SHIP. Two isomeric ...states with half-lives of 88(6) ms and 11.5(6) ms, respectively, and with complex {alpha}-decay schemes were identified in {sup 192}At. The decay pattern of one of the isomers suggests that it is based on the oblate-deformed {pi}2f{sub 7/2}x{nu}1i{sub 13/2} configuration, which confirms the expected onset of deformation in the At isotopes by approaching the neutron midshell at N=104.
A pure neutron-rich {sup 26}Ne beam was obtained at the ISOLDE facility using isobaric selectivity. This was achieved by a combination of a plasma ion source with a cooled transfer line and ...subsequent mass separation. The high quality of the beam and good statistics allowed us to obtain new experimental information on the {sup 26}Ne {beta}-decay properties and resolve a contradiction between earlier experimental data and prediction of shell-model calculations.
The {beta}-decay properties of {sub 28}{sup 72}Ni{sub 44} and {sub 29}{sup 72}Cu{sub 43} have been studied at the LISOL facility of Louvain-La-Neuve and at the CERN-ISOLDE facility, respectively. ...These neutron-rich nuclei have been produced in the proton-induced fission of {sup 238}U. Their decay schemes are presented and the lifetime T{sub 1/2}=6.63(3) s of {sup 72}Cu was measured. No {beta}-decaying isomeric state was found in {sup 72}Cu, in line with a suggested spin (2) for its ground state. Spin and parity assignments of the observed excited states in the odd-odd nucleus {sup 72}Cu are proposed and discussed in terms of coupling between the valence proton and neutrons. Comparison is made with a schematic shell-model picture of {sup 72}Cu and with large-scale shell-model calculations performed in the (2p{sub 3/2}1f{sub 5/2}2p{sub 1/2}1g{sub 9/2}) shell space outside the doubly magic {sub 28}{sup 56}Ni{sub 28} core.
We report on the observation of a new isomeric state in \(^{68}\)Ni. We suggest that the newly observed state at 168(1) keV above the first 2\(^+\) state is a \(\pi(2p-2h)\) 0\(^{+}\) state across ...the major Z=28 shell gap. Comparison with theoretical calculations indicates a pure proton intruder configuration and the deduced low-lying structure of this key nucleus suggests a possible shape coexistence scenario involving a highly deformed state.
We report here the first direct lifetime measurement of the 2+1 state in 72,74Zn. The neutron-rich beam was produced by in-flight fragmentation of 76Ge at the Grand Accélérateur National d'Ions ...Lourds and separated with the LISE spectrometer. The 2+1 state was excited by inelastic scattering and knock-out reaction on a CD2 target and its lifetime was measured by the recoil-distance Dopplershift method with the K\"oln plunger device combined with the EXOGAM detectors. The lifetimes of the 2+1 states in 72,74Zn were determined to be 17.9(18) and 27.0(24) ps, which correspond to reduced transition probabilities B(E2; 2+1 \rightarrow 0+) = 385(39) and 370(33) e2fm4, respectively. These values support the idea of a systematic maximum of collectivity at N = 42 for Zn, Ge and Se nuclei. In addition, the available systematics in the neighboring nuclei point towards a transition from a spherical oscillator at N = 40 to complete {\gamma}-softness at N = 42.
A pure neutron-rich 26Ne beam was obtained at the ISOLDE facility using isobaric selectivity. This was achieved by a combination of a plasma ion source with a cooled transfer line and subsequent mass ...separation. The high quality of the beam and good statistics allowed us to obtain new experimental information on the 26Ne β-decay properties and resolve a contradiction between earlier experimental data and prediction of shell-model calculations.
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