High spin states and evidence for octupole correlations in $^{\bf 117}$Xe

Z. Liu; X. Sun; X. Zhou; X. Lei; Y. Guo; Y. Zhang; X. Chen; H. Jin; Y. Luo; S.X. Wen; C.X. Yang; G.J. Yuan; G.S. Li; X.A. Liu; W.D. Luo; Y.S. Chen

doi:doi:10.1007/s100500050042

2022 Impact factor 2.7

Hadrons and Nuclei

Eur. Phys. J. A 1, 125-135

High spin states and evidence for octupole correlations in ¹¹⁷Xe

Z. Liu¹ - X. Sun¹ - X. Zhou¹ - X. Lei¹ - Y. Guo¹ - Y. Zhang¹ - X. Chen¹ - H. Jin¹ - Y. Luo¹ - S.X. Wen² - C.X. Yang² - G.J. Yuan² - G.S. Li² - X.A. Liu² - W.D. Luo² - Y.S. Chen²

¹ Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, People's Republic of China
² China Institute of Atomic Energy, Beijing 102413, People's Republic of China

Received: 17 June 1997 / Revised version: 29 September 1997 Communicated by B. Herskind

Abstract
High-spin states of ¹¹⁷Xe were investigated by means of in-beam $\gamma -$ ray spectroscopic techniques via the reaction of ²⁸Si bombarding a ⁹²Mo target at beam energies of 100-120 MeV. A positive-parity rotational band decaying into the yrast negative-parity band by a series of enhanced E1 transitions was observed for the first time, implying the existence of octupole correlations in ¹¹⁷Xe. The B(E1) values increase with spin. The $\nu$ d_5/2 band was firmly established up to 27/2⁺ and the B(M1)/B(E2) ratios were extracted from the relative intensities of $\gamma$ -rays in this band. The previously known $\nu$ h_11/2 and $\nu$ g_7/2 [413]5/2⁺ $\alpha =-$ 1/2 bands were confirmed and extended up to high spins and two bandcrossings are observed in the latter at $\hbar \omega$ =0.33 and 0.44 MeV, respectively. The bandcrossings and configurations of these bands are discussed by TRS and CSM calculations. In a $\gamma -\gamma -t$ measurement, the 11/2^- and 7/2^- levels were identified as two isomers with half-lives of 59.4 $\pm$ 20 ns and 16.5 $\pm$ 8.0 ns, respectively.