By studying the (109)Xe→(105)Te→(101)Sn superallowed α-decay chain, we observe low-lying states in (101)Sn, the one-neutron system outside doubly magic (100)Sn. We find that the spins of the ground state (J=7/2) and first excited state (J=5/2) in (101)Sn are reversed with respect to the traditional level ordering postulated for (103)Sn and the heavier tin isotopes. Through simple arguments and state-of-the-art shell-model calculations we explain this unexpected switch in terms of a transition from the single-particle regime to the collective mode in which orbital-dependent pairing correlations dominate.

Two-dimensional coherent structures in potential and saturation current have been observed in the turbulent plasma of the simple magnetized torus Blaamann, using the conditional averaging technique. The structures observed in helium plasmas are evolving in time and rotating in the poloidal cross-section with a period of about 100 µs. The time resolved average radial particle transport generated by these structures has been calculated, and it is shown that large bursty flux events occur at the vortex separatrices whenever a double vortex in the potential is formed. The time evolution of fluxes has been correlated with the dynamical evolution of the structures and their topology. The results suggest that the intermittent behaviour of the transport is due to events involving the dynamics of coherent structures on a short-timescale. The observed structures are temporally intermittent. When they occur, they cover most of the plasma cross-section.

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Isobarically purified beams of 77 Cu with energies of 225 and 0.2 MeV were used at the Holifield Radioactive Ion Beam Facility of Oak Ridge National Laboratory to study β decay into states in 77 Zn. Data taken at 225 MeV allowed the determination of absolute branching ratios relative to the decay of 77 Cu for this β decay as well as its daughters. From these we obtained a refined β-delayed neutron emission probability of 30.3( 22)% and a probability that the decay proceeds through 77 Zn g of 49.1(26)%. A total of 64 γ rays were placed in a level scheme for 77 Zn containing 35 excited states including one state above the neutron separation energy, whereas two γ rays were observed for the βn branch to states in 76 Zn. The growth and decay curves of some prominent γ rays indicate a single β-decaying state with a half-life of 480( 9) ms. The decay pattern for 77 Cu, with observed feeding of 8(3)% to 7/2 + 77 Zn g and 6(3)% to 1/2 − 77 Zn m , in contrast to the large feeding observed for decay of πp 3/2 73 Cu g to 1/2 − 73 Zn g , strongly suggests a πf 5/2 ground state for the studied 77 Cu activity.