학술논문
K-mixing in the doubly mid-shell nuclide 170Dy and the role of vibrational degeneracy
Document Type
article
Author
P.-A. Söderström; P.M. Walker; J. Wu; H.L. Liu; P.H. Regan; H. Watanabe; P. Doornenbal; Z. Korkulu; P. Lee; J.J. Liu; G. Lorusso; S. Nishimura; V.H. Phong; T. Sumikama; F.R. Xu; A. Yagi; G.X. Zhang; D.S. Ahn; T. Alharbi; H. Baba; F. Browne; A.M. Bruce; R.J. Carroll; K.Y. Chae; Zs. Dombradi; A. Estrade; N. Fukuda; C.J. Griffin; E. Ideguchi; N. Inabe; T. Isobe; H. Kanaoka; S. Kanaya; I. Kojouharov; F.G. Kondev; T. Kubo; S. Kubono; N. Kurz; I. Kuti; S. Lalkovski; G.J. Lane; E.J. Lee; C.S. Lee; G. Lotay; C.-B. Moon; I. Nishizuka; C.R. Niţă; A. Odahara; Z. Patel; Zs. Podolyák; O.J. Roberts; H. Sakurai; H. Schaffner; C.M. Shand; H. Suzuki; H. Takeda; S. Terashima; Zs. Vajta; J.J. Valiente-Dòbon; Z.Y. Xu
Source
Physics Letters B, Vol 762, Iss , Pp 404-408 (2016)
Subject
Language
English
ISSN
0370-2693
Abstract
A detailed study of the structure of the doubly mid-shell nucleus Dy104166170 has been carried out, following isomeric and β decay. We have measured the yrast band up to the spin-parity Jπ=6+ state, the K=2 γ-vibration band up to the 5+ state, a low-lying negative-parity band based on a 2− state that could be a candidate for the lowest energy octupole vibration state within this nucleus, and a candidate for the Kπ=6+ two quasi-particle isomer. This state was determined to have an excitation energy of 1643.91(23) keV and a half life of 0.99(4) μs, with a reduced hindrance for its decay to the ground-state band an order of magnitude lower than predicted by NpNn systematics. This is interpreted as being due to γ-vibrational mixing from a near degeneracy of the isomer and the 6+ state of the γ band. Furthermore, the parent nucleus 170Tb has been determined to have a half-life of 0.91(−13+18) s with a possible spin-parity of 2−. Keywords: K isomer, Dysprosium, Mid-shell, γ-Ray spectroscopy