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Yrast states up to (6+) in the neutron-rich S40 nucleus have been studied using binary grazing reactions produced by the interaction of a 215 MeV beam of S36 ions with a thin Pb208 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 0 ω sd-pf shell-model calculations indicates that one- and two-proton excitations from the 2s1/2 to the 1d3/2 orbitals play an important role in reproducing the S40 yrast level structure and the published B(E2;0g.s.+→21+) 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 0 ω sd-pf shell-model calculations. © 2010 The American Physical Society. ; Supported in part by the EPSRC (UK) and by the European Union under Contract No. RII3-CT-2004-506065. Support from STFC. Support from ORSAS and from the University of the West of Scotland. Support from the Spanish Ministerio de Ciencia e Innovación under Contract Nos. FPA2007-66069 and FPA2009-13377-C02-02. Support from OTKA Project No. K68801. ; Peer Reviewed

Yrast states in the neutron-rich S41 nucleus have been studied using binary grazing reactions produced by the interaction of a 215-MeV beam of S36 ions with a thin Pb208 target. The magnetic spectrometer, PRISMA, and the γ-ray array, CLARA, were used in the measurements. γ-ray transitions of energy 449 and 638 keV were observed. Results from published intermediate-energy Coulomb excitation measurements in combination with those from the present work have led to the construction of a new S41 level scheme. Proposed Jπ values are based on experimental observation and on model-dependent arguments. The level scheme and published electromagnetic transition probabilities are discussed within the context of state-of-art shell-model calculations using the SDPF-U effective interaction. In contrast with the excellent agreement observed in earlier published work, here there are significant discrepancies between experiment and the results of shell-model calculations. © 2011 American Physical Society. ; Supported in part by the EPSRC (UK) and by the European Union under Contract No. RII3-CT- 2004-506065. A.J. acknowledges financial support from the m Spanish Ministerio de Ciencia e Innovacion under Contracts No. FPA2007-66069 and No. FPA2009-13377-C02-02. Zs.D. acknowledges the financial support from OTKA Project No. K68801. ; Peer Reviewed

R. Chapman et al. ; 8 págs.; 6 figs.; 1 tab. ; The neutron-rich S39 nucleus has been studied using binary grazing reactions produced by the interaction of a 215-MeV beam of S36 ions with a thin Pb208 target. The magnetic spectrometer, PRISMA, and the γ-ray array, CLARA, were used in the measurements. Gamma-ray transitions of the following energies were observed: 339, 398, 466, 705, 1517, 1656, and 1724 keV. Five of the observed transitions have been tentatively assigned to the decay of excited states with spins up to (11/2-). The results of a state-of-the-art shell-model calculation of the level scheme of S39 using the SDPF-U effective interaction are also presented. The systematic behavior of the excitation energy of the first 11/2- states in the odd-A isotopes of sulfur and argon is discussed in relation to the excitation energy of the first excited 2+ states of the adjacent even-A isotopes. The states of S39 that have the components in their wave functions corresponding to three neutrons in the 1f7/2 orbital outside the N=20 core have also been discussed within the context of the 0 ω shell-model calculations presented here. ©2016 American Physical Society ; This work was supported in part by the EPSRC (UK) and by the European Union under Contract No. RII3-CT- 2004-506065. Five of us (D.O., M.B., A.H., K.K., and A.P.) acknowledge financial support from the EPSRC. Z.M.W. acknowledges support from ORSAS and from the University of the West of Scotland. A.N.D. acknowledges support from the STFC. A.J. acknowledges financial support from the Spanish Ministerio de Ciencia e Innovación under Contracts No. FPA2007-66069 and No. FPA2009-13377-C02-02. Zs.D. acknowledges financial support from OTKA under Project No. K100835. S.S. acknowledges support from the Croatian Science Foundation under Project No. 7194. The contribution of the accelerator and target-fabrication staff at the INFN Legnaro National Laboratory is gratefully acknowledged. ; Peer Reviewed

Yrast states in the neutron-rich 1433Si19 nucleus have been studied using binary grazing reactions produced by the interaction of a 215-MeV beam of S36 ions with a thin Pb208 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 Si33 level scheme. The experimental level scheme is compared with the results of 1ω 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 Si33 is discussed within the context of an odd neutron coupled to states of the Si32 core. © 2010 The American Physical Society. ; This work was supported in part by the EPSRC (UK) and by the European Union under Contract No. RII3-CT-2004-506065. Five of us (D.O., M.B., A.H., K.K., and A.P.)acknowledge financial support from the EPSRC. Z.M.W acknowledges support from ORSAS and from the University of the West of Scotland. A.J. acknowledges financial supportfrom the Spanish Ministerio de Ciencia e Innovación under Contract Nos. FPA2007-66069 and FPA2009-13377-C02-02. Zs.D. acknowledges the financial support from OTKA Project No. K68801. ; Peer Reviewed

13 pags., 12 figs., 4 tabs. ; Transition probabilities of intermediate-spin yrast and non-yrast excitations in Se80,82 were investigated in a recoil distance Doppler-shift (RDDS) experiment performed at the Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Legnaro. The Cologne Plunger device for deep inelastic scattering was used for the RDDS technique and was combined with the AGATA Demonstrator array for the γ-ray detection and coupled to the PRISMA magnetic spectrometer for an event-by-event particle identification. In Se80, the level lifetimes of the yrast (61+) and (81+) states and of a non-yrast band feeding the yrast 41+ state are determined. A spin and parity assignment of the head of this sideband is discussed based on the experimental results and supported by large-scale shell-model calculations. In Se82, the level lifetimes of the yrast 61+ state and the yrare 42+ state and lifetime limits of the yrast (101+) state and of the 51- state are determined. Although the experimental results contain large uncertainties, they are interpreted with care in terms of large-scale shell-model calculations using the effective interactions JUN45 and jj44b. The excited states' wave functions are investigated and discussed with respect to the role of the neutron g9/2 orbital. ; This work was partially supported by the European Union Seventh Framework Program FP7/2007-2013 under Grant Agreement No. 262010 ENSAR, by the German Research Foundation (DFG) under Contract No. DE 1516/3-1, by the German BMBF under Grant No. 05P15PKFNA and by the Spanish Ministerio de Economía y Competitividad under Contract No. FPA2014-57196-C5-4-P. J.L. and A.V. thank the Bonn-Cologne Graduate School of Physics and Astronomy (BCGS) for financial support. ; Peer Reviewed