Decay of a 19(-) isomeric state in Lu-156


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Lewis M. C. , Parr E., Page R. D. , McPeake C., Joss D. T. , Ali F. A. , ...More

PHYSICAL REVIEW C, vol.98, no.2, 2018 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 98 Issue: 2
  • Publication Date: 2018
  • Doi Number: 10.1103/physrevc.98.024302
  • Title of Journal : PHYSICAL REVIEW C

Abstract

A multiparticle spin-trap isomeric state having a half-life of 179(4) ns and lying 2601 keV above the yrast 10(+) state in Lu-156 has been discovered. The Lu-156 nuclei were produced by bombarding isotopically enriched Cd-106 targets with beams of Ni-58 ions, separated in flight using the gas-filled separator RITU and their decays were measured using the GREAT spectrometer. Analysis of the main decay path that populates yrast states observed previously suggests a spin-parity assignment of 19(-) for the isomeric state, which is consistent with isomeric states identified in the N = 85 isotones. Comparison with other decay paths in Lu-156 indicates that the [pi h(11/)(2)(-1) circle times nu h(9/2)]10(+) state at the bottom of the yrast sequence is likely to be the a-decaying isomeric state, with the [pi h(11/)(2)(-1) circle times nu f(7/2)]9(+) state lying 62 keV above it. The relative ordering of the lowest-lying 9(+) and 10(+) states is inverted in Lu-156 compared with its odd-odd isotones.