Identification of yrast high-K intrinsic states in 188Os

Abstract

The high-spin structure of the Z = 76 nucleus 188Os has been studied using the incomplete fusion reaction 7Li + 186W. A Kπ = 10+ band has been established up to spin (24+) and its crossing with the ground-state band has been studied. In addition, intrinsic high-K states have been identified and on top of two of them, Kπ = 7− and Kπ = 10−, regular bands have been observed. The Kπ = 16+ and Kπ = 18+ states are yrast whereas the Kπ = 14+ level lies only 33 keV above the yrast line and decays with a low reduced hindrance of fν < 1.3 to the ground-state band ( K = 14). The results are discussed by means of a systematic comparison with the even-even neighboring nucleus 186Os. Configuration-constrained multiquasiparticle potential-energy-surface calculations have been performed to identify the configurations of multiquasiparticle states.