Bianco, L.Page, R. D.Darby, I. G.Joss, D. T.Simpson, J.Al-Khalili, J. J.Greenlees, P. T.2019-08-012019-08-0120100370-2693https://dx.doi.org/10.1016/j.physletb.2010.04.056https://hdl.handle.net/11480/4871The nuclides W-157 and Os-161 have been discovered ill reactions of Ni-58 ion beams with a Cd-106 target. The Os-161 alpha-decay energy and half-life were 6890 +/- 12 keV and 640 +/- 60 mu s. The daughter W-157 nuclei beta-decayed with a half-life of 275 +/- 40 ms, populating both low-lying alpha-decaying states in Ta-157, which is consistent with a 7/2(-) ground state in W-157. Fine structure observed in the alpha decay of Os-161 places the lowest excited state in W-157 with 1(pi) = 9/2(-) at 318 +/- 30 key. The branching ratio of 5.5(-2.2)(+3.1)% indicates that Os-161 also has a 7/2(-) ground state. Shell-model calculations analysing the effects of monopole shifts and a tensor force on the relative energies of 2f(7/2) and 1h(9/2) neutron states in N = 83 isotones are presented. (C) 2010 Elsevier B.V. All rights reserved.eninfo:eu-repo/semantics/closedAccessNUCLEAR REACTIONS Ni-58+Cd-106 at 290, 300, 310 MeV beam energy, gas-filled recoil separator, Si detectorsMeasured E alpha, t(1/2)Deduced neutron single-particle configurations in Os-161, W-157Shell model calculationsArticle6901151810.1016/j.physletb.2010.04.0562-s2.0-77953477653Q1WOS:000278933900003Q1