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A program of nuclear structure studies to support fundamental symmetry tests has been initiated. Motivated by the search for an electric dipole moment in 199Hg, the structure in the vicinity has been explored via direct reaction studies. To date, these have included the 198,200 Hg(d, d') inelastic scattering reactions, with the aim to obtain information on the E2 and E3 strength distributions, and the 198Hg(d, p) and 200Hg(d, t) reactions to obtain information on the single-particle states in 198Hg. The studies using the 200Hg targets have been fully analyzed using the FRESCO reaction code yielding the E2 and E3 strength distribution to 4 MeV in excitation energy, and the (d, t) single- particle strength to over 3 MeV in excitation energy. [ABSTRACT FROM AUTHOR]

The nuclear structure of 122Xe has been investigated with measurements of the β+/EC decay of 122Cs with the 8π γ-ray spectrometer at the TRIUMF-ISAC facility. The data collected have enabled the determination of relative B(E2) values of some low-energy transitions, and the in-band transitions of the excited 0+ bands have been observed. As a result, the 2+ rotational band members for the 0+2 and 0+3 states have been firmly identified. [ABSTRACT FROM AUTHOR]

Many efforts have been made in nuclear structure physics to interpret the nature of low-lying excited 0+ states in well-deformed rare-earth nuclei. However, one of the difficulties in resolving the nature of these states is that there is a paucity of data. In this work, excited 0+ states in the N = 92 nucleus 160Er were studied via the 162Er(p, t)160Er two-neutron transfer reaction, which is ideal for probing 0+ → 0+ transitions, at the Maier-Leibnitz-Laboratorium in Garching, Germany. Reaction products were momentum-analyzed with a Quadrupole-3-Dipole magnetic spectrograph. The 0+2 state was observed to be strongly populated with 18% of the ground state strength. [ABSTRACT FROM AUTHOR]

The structures of 3+ states in Os have been debated over several decades. Based on measured B(E2) values they were interpreted in 186–192Os as Kπ = 4+ two-phonon vibrations, whereas inelastic scattering, and (t,α) work imply a hexadecapole phonon description. To clarify the nature of these Kπ = 4+ bands in 186,188Os, we performed a (3He,d) reaction on 185,187Re targets using 30 MeV 3He beams and a Q3D spectrograph. Absolute cross sections were obtained for excited states up to 3 MeV at 9 angles from 5° to 50°. Results indicate a significant 52+[402]π+32+[402]π component in agreement with quasiparticle phonon model predictions for a single hexadecapole phonon structure. [ABSTRACT FROM AUTHOR]

Recent experiments with GAMMASPHERE and the MICROBALL charged-particle detector array have led to the identification, and have enabled the detailed spectroscopic study, of highly-deformed and superdeformed rotational bands in a number of A ∼ 40, N ≈ Z nuclei. These rotational bands are built on multi-particle multi-hole excitations across the N, Z = 20 shell gap from the sd to the pf shell and, in the context of the Nilsson scheme, are associated with the shell gaps formed at large prolate deformation for particle numbers N, Z = 16, 18,20 as pf-shell intruder orbitals are occupied. In analogy with well-developed rotational motion in heavy nuclei, these highly collective rotational structures involve active valence particles in two major shells for both protons and neutrons, yet the A ∼ 40 bands possess the unique advantage that the valence space dimension remains small enough to be approached from a shell-model perspective. These rotational bands thus provide an ideal opportunity for detailed comparisons between experimental data and both microscopic and macroscopic models of collective motion in nuclei. [ABSTRACT FROM AUTHOR]

In response to new opportunities presented by re-accelerated beams from the ISAC-II facility at TRIUMF, a plunger-type Recoil Distance Method device, the TIGRESS Integrated Plunger, is under construction to be used with the TIGRESS segmented germanium array. An experimental program aimed in nuclear structure measurements along the N=Z line is planned. Lifetime measurements in the shape-coexistence region near N∼Z∼36 are anticipated to provide information of significance to Vud matrix element evaluation from superallowed beta-decay measurements. [ABSTRACT FROM AUTHOR]