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Proton inelastic scattering on the neutron-rich nucleus 32Mg has been experimentally studied at Elab = 46.5 MeV/nucleon in inverse kinematics. The energies of excited states in 32Mg were obtained by measuring de-excitation γ rays. Several new states were identified by γ-γ coincidence analysis. Their spins and parities were restricted and the deformation parameters βp,p′ were extracted from the measured angular distribution of the proton inelastic scattering. The present analysis favors 4+ for the spin and parity of the 2321-keV state. [ABSTRACT FROM AUTHOR]

Coulomb excitation of the exotic neutron-rich nucleus 26Ne on a 208Pb target was measured at 58 A.MeV in order to search for low-lying E1 strength above the neutron emission threshold. The radioactive beam was produced by fragmentation of a 95 A.MeVAr beam delivered by the RIKEN Accelerator Research Facility. The set-up included a NaI(Tl) gamma-ray array, a charged fragment hodoscope and a neutron wall. Using the invariant mass method in the 25Ne+n channel, we observe by multipole decomposition a sizable amount of E1 strength between 6 and 10 MeV excitation energy. For the first time, the decay pattern of low-lying strength in a neutron-rich nucleus is measured. [ABSTRACT FROM AUTHOR]

Structure of the neutron-rich Ge isotopes at and around N = 50 has been investigated via intermediate-energy Coulomb excitation using secondary beams of 78-82Ge incident on a Pb target. The B( E2) values for the low-lying 2+ states have been extracted and compared with the data for neighboring isotopes around N = 50. In addition, a new method of intermediate-energy two-step Coulomb excitation has been proposed as a spectroscopic tool to study the 4+ states in neutron-rich even-even nuclei. The first application of the method and its results are presented. [ABSTRACT FROM AUTHOR]

Abstract: The structure of the neutron rich pf-shell nuclei 58Ti36, 60Cr36 and 62Cr38 was studied by proton inelastic scattering in inverse kinematics. Large quadrupole deformation lengths of 1.12(16) fm and 1.36(14) fm were obtained for 60Cr and 62Cr, respectively, which confirm the enhanced collectivity in these nuclei. An excited state was observed in 62Cr at 1180(10) keV with tentative assignment of . The increase in the ratio indicates that the nature of collectivity changes from vibrational to rotational in 62Cr and affords evidence for the development of static deformation. The excitation energy of the newly observed 2+ state in 58Ti (1046(17) keV) shows hindered collectivity. The contrast between the structures of Cr and Ti suggests that the contributions of both protons and neutrons are crucial for the large collectivity in Cr close to . From the comparison to shell model calculations, the large collectivity is found to originate from the admixture of the pf- and gd-shells across the sub-shell gap. [Copyright &y& Elsevier]