University of Surrey

Test tubes in the lab Research in the ATI Dance Research

Interplay of quasiparticle and vibrational excitations: First observation of isomeric states in ¹⁶⁸Dy and ¹⁶⁹Dy

Zhang, G.X., Watanabe, H., Dracoulis, G.D., Kondev, F.G., Lane, G.J., Regan, P.H., Söderström, P.-A., Walker, P.M., Yoshida, K., Kanaoka, H. , Korkulu, Z., Lee, P.S., Liu, J.J., Nishimura, S., Wu, J., Yagi, A., Ahn, D.S., Alharbi, T., Baba, H., Browne, F., Bruce, A.M., Carpenter, M.P., Carroll, R.J., Chae, K.Y., Chiara, C.J., Dombradi, Zs., Doornenbal, P., Estrade, A., Fukuda, N., Griffin, C., Ideguchi, E., Inabe, N., Isobe, T., Kanaya, S., Kojouharov, I., Kubo, T., Kubono, S., Kurz, N., Kuti, I., Lalkovski, S., Lauritsen, T., Lee, C.S., Lee, E.J., Lister, C.J., Lorusso, G., Lotay, G., McCutchan, E.A., Moon, C.-B., Nishizuka, I., Nita, C.R., Odahara, A., Patel, Z., Phong, V.H., Podolyak, Zs., Roberts, O.J., Sakurai, H., Schaffner, H., Seweryniak, D., Shand, C.M., Shimizu, Y., Sumikama, T., Suzuki, H., Takeda, H., Terashima, S., Vajta, Zs., Valiente-Dóbon, J.J., Xu, Z.Y. and Zhu, S. (2019) Interplay of quasiparticle and vibrational excitations: First observation of isomeric states in ¹⁶⁸Dy and ¹⁶⁹Dy Physics Letters B, 799, 135036. pp. 1-7.

manuscript_168169Dy_accept.pdf - Accepted version Manuscript
Available under License Creative Commons Attribution.

Download (517kB) | Preview


The neutron-rich dysprosium isotopes ¹⁶⁸Dy₁₀₂ and ¹⁶⁹Dy₁₀₃ have been investigated using the EURICA γ-ray spectrometer, following production via in-flight fission of a high-intensity uranium beam in conjunction with isotope separation through the BigRIPS separator at RIBF in RIKEN Nishina Center. For ¹⁶⁸Dy, a previously unreported isomer with a half-life of 0.57(7) μs has been identified at an excitation energy of 1378 keV, and its presence affirmed independently using γ-γ-γ coincidence data taken with Gammasphere via two-proton transfer from an enriched ¹⁷⁰Er target performed at Argonne National Laboratory. This isomer is assigned Jπ = Kπ = (4⁻) based on the measured transition strengths, decay patterns, and the energy systematics for two-quasiparticle states in N = 102 isotones. The underlying mechanism of two-quasiparticle excitations in the doubly midshell region is discussed in comparison with the deformed QRPA and multi-quasiparticle calculations. In ¹⁶⁹Dy, the B(E2) value for the transition de-exciting the previously unreported Kπ = (1/2⁻) isomeric state at 166 keV to the Kπ = (5/2⁻) ground state is approximately two orders of magnitude larger than the E2 strength for the corresponding isomeric-decay transition in the N = 103 isotone ¹⁷³Yb, suggesting the presence of a significant γ-vibrational admixture with a dominant neutron one-quasiparticle component in the isomeric state.

Item Type: Article
Divisions : Faculty of Engineering and Physical Sciences > Physics
Authors :
Zhang, G.X.
Watanabe, H.
Dracoulis, G.D.
Kondev, F.G.
Lane, G.J.
Söderström, P.-A.
Yoshida, K.
Kanaoka, H.
Korkulu, Z.
Lee, P.S.
Liu, J.J.
Nishimura, S.
Wu, J.
Yagi, A.
Ahn, D.S.
Alharbi, T.
Baba, H.
Browne, F.
Bruce, A.M.
Carpenter, M.P.
Carroll, R.J.
Chae, K.Y.
Chiara, C.J.
Dombradi, Zs.
Doornenbal, P.
Estrade, A.
Fukuda, N.
Griffin, C.
Ideguchi, E.
Inabe, N.
Isobe, T.
Kanaya, S.
Kojouharov, I.
Kubo, T.
Kubono, S.
Kurz, N.
Kuti, I.
Lalkovski, S.
Lauritsen, T.
Lee, C.S.
Lee, E.J.
Lister, C.J.
Lorusso, G.
McCutchan, E.A.
Moon, C.-B.
Nishizuka, I.
Nita, C.R.
Odahara, A.
Patel, Z.
Phong, V.H.
Roberts, O.J.
Sakurai, H.
Schaffner, H.
Seweryniak, D.
Shimizu, Y.
Sumikama, T.
Suzuki, H.
Takeda, H.
Terashima, S.
Vajta, Zs.
Valiente-Dóbon, J.J.
Xu, Z.Y.
Zhu, S.
Date : 22 October 2019
Funders : Science and Technology Facilities Council (STFC), UK National Measurement Office (PHR)
DOI : 10.1016/j.physletb.2019.135036
Copyright Disclaimer : © 2019 The Authors. Published by Elsevier B.V.
Depositing User : Clive Harris
Date Deposited : 06 Nov 2019 16:23
Last Modified : 06 Nov 2019 16:23

Actions (login required)

View Item View Item


Downloads per month over past year

Information about this web site

© The University of Surrey, Guildford, Surrey, GU2 7XH, United Kingdom.
+44 (0)1483 300800