Physics Letters B (Jun 2023)
Axial and triaxial degrees of freedom in 72Zn
- S. Hellgartner,
- D. Mücher,
- K. Wimmer,
- V. Bildstein,
- J.L. Egido,
- R. Gernhäuser,
- R. Krücken,
- A.K. Nowak,
- M. Zielińska,
- C. Bauer,
- M.L.L. Benito,
- S. Bottoni,
- H. De Witte,
- J. Elseviers,
- D. Fedorov,
- F. Flavigny,
- A. Illana,
- M. Klintefjord,
- T. Kröll,
- R. Lutter,
- B. Marsh,
- R. Orlandi,
- J. Pakarinen,
- R. Raabe,
- E. Rapisarda,
- S. Reichert,
- P. Reiter,
- M. Scheck,
- M. Seidlitz,
- B. Siebeck,
- E. Siesling,
- T. Steinbach,
- T. Stora,
- M. Vermeulen,
- D. Voulot,
- N. Warr,
- F.J.C. Wenander
Affiliations
- S. Hellgartner
- Physik-Department, Technische Universität München, 85748 Garching, Germany
- D. Mücher
- Institut für Kernphysik, Universität zu Köln, 50937 Köln, Germany; College of Physics & Engineering Science, University of Guelph, 50 Stone Road East Guelph, Ontario N1G 2W1, Canada; Physical Sciences Division, TRIUMF, Vancouver, British Columbia, V6T 2A3, Canada; Corresponding authors.
- K. Wimmer
- GSI Helmholtzzentrum für Schwerionenforschung, D-64291 Darmstadt, Germany; Instituto de Estructura de la Materia, CSIC, E-28006 Madrid, Spain; Department of Physics, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan; Corresponding authors.
- V. Bildstein
- College of Physics & Engineering Science, University of Guelph, 50 Stone Road East Guelph, Ontario N1G 2W1, Canada
- J.L. Egido
- Departamento de Física Teórica, Universidad Autónoma de Madrid, E-28049 Madrid, Spain
- R. Gernhäuser
- Physik-Department, Technische Universität München, 85748 Garching, Germany
- R. Krücken
- Nuclear Science Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
- A.K. Nowak
- Physik-Department, Technische Universität München, 85748 Garching, Germany
- M. Zielińska
- IRFU, CEA, Université Paris-Saclay, 91191 Gif-sur-Yvette, France
- C. Bauer
- Institut für Kernphysik, Technische Universität Darmstadt, Germany
- M.L.L. Benito
- ISOLDE, CERN, CH-1211, Geneva, Switzerland
- S. Bottoni
- Dipartimento di Fisica, Università degli Studi di Milano and INFN Sez. Milano, Milano I-20133, Italy; KU Leuven, Instituut voor Kern- en Stralingsfysica, 3001 Leuven, Belgium
- H. De Witte
- KU Leuven, Instituut voor Kern- en Stralingsfysica, 3001 Leuven, Belgium
- J. Elseviers
- KU Leuven, Instituut voor Kern- en Stralingsfysica, 3001 Leuven, Belgium
- D. Fedorov
- ISOLDE, CERN, CH-1211, Geneva, Switzerland
- F. Flavigny
- Normandie Univ, ENSICAEN, UNICAEN, CNRS/IN2P3, LPC Caen, 14000 Caen, France
- A. Illana
- Instituto de Estructura de la Materia, CSIC, E-28006 Madrid, Spain; Department of Physics, University of Jyväskylä, P.O. Box 35, FI-40014 Jyväskylä, Finland
- M. Klintefjord
- Department of Physics, University of Oslo, N-0316 Oslo, Norway
- T. Kröll
- Institut für Kernphysik, Technische Universität Darmstadt, Germany
- R. Lutter
- Department of Physics, Ludwig Maximilian Universität München, 85748 Garching, Germany
- B. Marsh
- ISOLDE, CERN, CH-1211, Geneva, Switzerland
- R. Orlandi
- Instituto de Estructura de la Materia, CSIC, E-28006 Madrid, Spain
- J. Pakarinen
- Department of Physics, University of Jyväskylä, P.O. Box 35, FI-40014 Jyväskylä, Finland
- R. Raabe
- KU Leuven, Instituut voor Kern- en Stralingsfysica, 3001 Leuven, Belgium
- E. Rapisarda
- KU Leuven, Instituut voor Kern- en Stralingsfysica, 3001 Leuven, Belgium; ISOLDE, CERN, CH-1211, Geneva, Switzerland; Paul Scherrer Institut, Villigen, Switzerland
- S. Reichert
- Physik-Department, Technische Universität München, 85748 Garching, Germany
- P. Reiter
- Institut für Kernphysik, Universität zu Köln, 50937 Köln, Germany
- M. Scheck
- School of Computing, Engineering, and Physical Sciences, University of the West of Scotland, Paisley PA1 2BE, UK
- M. Seidlitz
- Institut für Kernphysik, Universität zu Köln, 50937 Köln, Germany
- B. Siebeck
- Institut für Kernphysik, Universität zu Köln, 50937 Köln, Germany
- E. Siesling
- ISOLDE, CERN, CH-1211, Geneva, Switzerland
- T. Steinbach
- Institut für Kernphysik, Universität zu Köln, 50937 Köln, Germany
- T. Stora
- ISOLDE, CERN, CH-1211, Geneva, Switzerland
- M. Vermeulen
- Department of Physics, University of York, YO10 5DD, United Kingdom
- D. Voulot
- ISOLDE, CERN, CH-1211, Geneva, Switzerland
- N. Warr
- Institut für Kernphysik, Universität zu Köln, 50937 Köln, Germany
- F.J.C. Wenander
- ISOLDE, CERN, CH-1211, Geneva, Switzerland
- Journal volume & issue
-
Vol. 841
p. 137933
Abstract
The unstable N=42 nucleus 72Zn has been studied using multiple safe Coulomb excitation in inverse kinematics. The experiment was performed at the REX-ISOLDE facility at CERN making first use of the silicon detector array C-REX in combination with the γ-ray spectrometer Miniball. The high angular coverage of C-REX allowed to determine the reduced transition strengths for the decay of the yrast 01+, 21+ and 41+ as well as of the 02+ and 22+ states in 72Zn. The quadrupole moments of the 21+, 41+ and 22+ states were extracted. Using model independent quadrupole invariants, the ground state of 72Zn was found to have an average deformation in the γ degree of freedom close to maximum triaxiality. In comparison to experimental data in zinc isotopes with N<40, the collectivity of the 41+ state in neutron-rich 72Zn is significantly larger, indicating a collective yrast band based on the ground state of 72Zn. In contrast, a low experimental B(E2;02+→21+) strength was determined, indicating a different structure for the 02+ state. Shell-model calculations propose a 02+ state featuring a larger fraction of the (spherical) N=40 closed-shell configuration in its wave function than for the 01+ ground state.The results were also compared with beyond mean field calculations which corroborate the large deformation in the γ degree of freedom, while pointing to a more deformed 02+ state. These experimental and theoretical findings establish the importance of the γ degree of freedom in the ground state of 72Zn, located between the 68,70Ni nuclei that have spherical ground states, and 76Ge, which has a rigid triaxial shape.
