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Yrast states up to (6 + ) in the neutron-rich 40 S nucleus have been studied using binary grazing reactions produced by the interaction of a 215 MeV beam of 36 S ions with a thin 208 Pb target. The novel experimental setup that combines the large acceptance magnetic spectrometer, PRISMA, and the high-efficiency γ -ray detection array, CLARA, was used. A new γ -ray transition at an energy of 1572 keV was observed and tentatively assigned to the (6 + ) → (4 + ) transition. A comparison of experimental observations and the results of large-scale 0hω sd-pf shell-model calculations indicates that one-and two-proton excitations from the 2s 1/2 to the 1d 3/2 orbitals play an important role in reproducing the 40 S yrast level structure and the published B(E2; 0 + g.s. → 2 + 1 ) value. The structure of the yrast states of the even-A isotopes of sulfur is interpreted in terms of the configurations of valence protons and neutrons within the context of large-scale 0hω sd-pf shell-model calculations.

The yrast sequence of the neutron-rich dysprosium isotope 168 Dy has been studied using multinucleon transfer reactions following collisions between a 460-MeV 82 Se beam and an 170 Er target. The reaction products were identified using the PRISMA magnetic spectrometer and the γ rays detected using the CLARA HPGe-detector array. The 2 + and 4 + members of the previously measured ground-state rotational band of 168 Dy have been confirmed and the yrast band extended up to 10 + . A tentative candidate for the 4 + → 2 + transition in 170 Dy was also identified. The data on these nuclei and on the lighter even-even dysprosium isotopes are interpreted in terms of total Routhian surface calculations and the evolution of collectivity in the vicinity of the proton-neutron valence product maximum is discussed.

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Yrast states in the neutron-rich 33 14 Si 19 nucleus have been studied using binary grazing reactions produced by the interaction of a 215-MeV beam of 36 S ions with a thin 208 Pb target. An experimental setup that combines the large-acceptance magnetic spectrometer PRISMA and the high-efficiency γ -ray detection array CLARA was used in the experiment. Four new γ -ray photopeaks at energies of 971, 1724, 1772, and 2655 keV were observed and assigned to the 33 Si level scheme. The experimental level scheme is compared with the results of 1hω p-sd-pf large-scale shell-model calculations using the recently developed PSDPFB effective interaction; good agreement is obtained. The structure of the populated states of 33 Si is discussed within the context of an odd neutron coupled to states of the 32 Si core.