Eur. Phys. J. A (2000) 8: 165-176
https://doi.org/10.1007/s100530050022

Co-existing coupling schemes at high spin in ¹⁶⁶Hf

¹ The Niels Bohr Institute, Blegdamsvej 17, DK-2100, Copenhagen Ø, Denmark
² Institut für Strahlen- und Kernphysik, University of Bonn, Bonn, Germany
³ Mississippi State University, Mississippi State, MS, 39762, USA
⁴ Dipartemento di Fisica, Università di Milano and INFN Milano, Milano, Italy
⁵ Laboratori Nationali Legnaro and INFN Padova, Padova, Italy
⁶ Niewodniczanski Institute of Nuclear Physics, Krakow, Poland
⁷ Institute of Nuclear Research (ATOMKI), H-4001, Debrecen, Hungary
⁸ Oliver Lodge Laboratory, University of Liverpool, Liverpool, UK
⁹ School of Sciences, Staffordshire University, College Road, Stoke-on-Trent, ST4 2DE, UK
¹⁰ CENBG, University of Bordeaux I., Bordeaux-Gradignan, France

Received: 6 April 2000
Published online: 15 June 2000

Abstract

The nucleus ¹⁶⁶Hf has been populated by the reaction ⁹⁶Zr(⁷⁴Ge,4n) using a beam energy of 310MeV. γ-rays were detected with the EUROBALL III detector array. Fourteen new normal-deformed rotational bands, of which six form coupled pairs, have been observed in ¹⁶⁶Hf. Four previously known bands have been extended to considerably higher spin, and configurations of the new bands are proposed. Two different bands have been assigned configurations involving the same orbitals at high spin. The two coupling schemes, deformation and rotation alignment, are discussed in connection with this new observation, which calls for a formulation of co-existing coupling schemes in six-quasiparticle structures involving the same orbitals at high spin.