Physics Letters B (Jun 2018)
Is seniority a partial dynamic symmetry in the first νg9/2 shell?
- A.I. Morales,
- G. Benzoni,
- H. Watanabe,
- G. de Angelis,
- S. Nishimura,
- L. Coraggio,
- A. Gargano,
- N. Itaco,
- T. Otsuka,
- Y. Tsunoda,
- P. Van Isacker,
- F. Browne,
- R. Daido,
- P. Doornenbal,
- Y. Fang,
- G. Lorusso,
- Z. Patel,
- S. Rice,
- L. Sinclair,
- P.-A. Söderström,
- T. Sumikama,
- J.J. Valiente-Dobón,
- J. Wu,
- Z.Y. Xu,
- A. Yagi,
- R. Yokoyama,
- H. Baba,
- R. Avigo,
- F.L. Bello Garrote,
- N. Blasi,
- A. Bracco,
- A.M. Bruce,
- F. Camera,
- S. Ceruti,
- F.C.L. Crespi,
- M.-C. Delattre,
- Zs. Dombradi,
- A. Gottardo,
- T. Isobe,
- I. Kojouharov,
- N. Kurz,
- I. Kuti,
- S. Lalkovski,
- K. Matsui,
- B. Melon,
- D. Mengoni,
- T. Miyazaki,
- V. Modamio-Hoybjor,
- S. Momiyama,
- D.R. Napoli,
- M. Niikura,
- R. Orlandi,
- Zs. Podolyák,
- P.H. Regan,
- H. Sakurai,
- E. Sahin,
- D. Sohler,
- H. Schaffner,
- R. Taniuchi,
- J. Taprogge,
- Zs. Vajta,
- O. Wieland,
- M. Yalcinkaya
Affiliations
- A.I. Morales
- Dipartimento di Fisica dell'Università degli Studi di Milano, Via Celoria 16, 20133 Milano, Italy; Istituto Nazionale di Fisica Nucleare, Sezione di Milano, Via Celoria 16, 20133 Milano, Italy; IFIC, CSIC-Universitat de València, E-46071 València, Spain; Corresponding author at: IFIC, CSIC-Universitat de València, E-46071 València, Spain.
- G. Benzoni
- Istituto Nazionale di Fisica Nucleare, Sezione di Milano, Via Celoria 16, 20133 Milano, Italy
- H. Watanabe
- IRCNPC, School of Physics and Nuclear Energy Engineering, Beihang University, Beijing 100191, China; RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
- G. de Angelis
- Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Legnaro, I-35020 Legnaro, Italy
- S. Nishimura
- RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
- L. Coraggio
- Istituto Nazionale di Fisica Nucleare, Sezione di Napoli, Napoli, Italy
- A. Gargano
- Istituto Nazionale di Fisica Nucleare, Sezione di Napoli, Napoli, Italy
- N. Itaco
- Istituto Nazionale di Fisica Nucleare, Sezione di Napoli, Napoli, Italy; Dipartimento di Matematica e Fisica dell'Università degli Studi della Campania, I-81100 Caserta, Italy
- T. Otsuka
- Center for Nuclear Study, The University of Tokyo, Bunkyo-ku, 113-0033 Tokyo, Japan; Department of Physics, The University of Tokyo, Bunkyo-ku, 113-0033 Tokyo, Japan; National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, MI 48824, USA; Instituut voor Kern- en Stralingsfysica, Katholieke Universiteit Leuven, B-3001 Leuven, Belgium
- Y. Tsunoda
- Center for Nuclear Study, The University of Tokyo, Bunkyo-ku, 113-0033 Tokyo, Japan
- P. Van Isacker
- Grand Accélérateur National d'Ions Lourds, CEA/DRF-CNRS/IN2P3, BP 55027, F-14076 Caen Cedex 5, France
- F. Browne
- School of Computing, Engineering and Mathematics, University of Brighton, Brighton, United Kingdom; RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
- R. Daido
- Department of Physics, Osaka University, Osaka, 560-0043 Toyonaka, Japan
- P. Doornenbal
- RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
- Y. Fang
- Department of Physics, Osaka University, Osaka, 560-0043 Toyonaka, Japan
- G. Lorusso
- RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
- Z. Patel
- Department of Physics, University of Surrey, Guildford GU2 7XH, United Kingdom; RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
- S. Rice
- Department of Physics, University of Surrey, Guildford GU2 7XH, United Kingdom; RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
- L. Sinclair
- Department of Physics, University of York, Heslington, York YO10 5DD, United Kingdom; RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
- P.-A. Söderström
- RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
- T. Sumikama
- Department of Physics, Tohoku University, Miyagi 980-8578, Japan
- J.J. Valiente-Dobón
- Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Legnaro, I-35020 Legnaro, Italy
- J. Wu
- RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
- Z.Y. Xu
- Department of Physics, The University of Tokyo, Bunkyo-ku, 113-0033 Tokyo, Japan; RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
- A. Yagi
- Department of Physics, Osaka University, Osaka, 560-0043 Toyonaka, Japan
- R. Yokoyama
- Department of Physics, The University of Tokyo, Bunkyo-ku, 113-0033 Tokyo, Japan
- H. Baba
- RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
- R. Avigo
- Dipartimento di Fisica dell'Università degli Studi di Milano, Via Celoria 16, 20133 Milano, Italy; Istituto Nazionale di Fisica Nucleare, Sezione di Milano, Via Celoria 16, 20133 Milano, Italy
- F.L. Bello Garrote
- Department of Physics, University of Oslo, N-0316 Oslo, Norway
- N. Blasi
- Istituto Nazionale di Fisica Nucleare, Sezione di Milano, Via Celoria 16, 20133 Milano, Italy
- A. Bracco
- Dipartimento di Fisica dell'Università degli Studi di Milano, Via Celoria 16, 20133 Milano, Italy; Istituto Nazionale di Fisica Nucleare, Sezione di Milano, Via Celoria 16, 20133 Milano, Italy
- A.M. Bruce
- School of Computing, Engineering and Mathematics, University of Brighton, Brighton, United Kingdom
- F. Camera
- Dipartimento di Fisica dell'Università degli Studi di Milano, Via Celoria 16, 20133 Milano, Italy; Istituto Nazionale di Fisica Nucleare, Sezione di Milano, Via Celoria 16, 20133 Milano, Italy
- S. Ceruti
- Dipartimento di Fisica dell'Università degli Studi di Milano, Via Celoria 16, 20133 Milano, Italy; Istituto Nazionale di Fisica Nucleare, Sezione di Milano, Via Celoria 16, 20133 Milano, Italy
- F.C.L. Crespi
- Dipartimento di Fisica dell'Università degli Studi di Milano, Via Celoria 16, 20133 Milano, Italy; Istituto Nazionale di Fisica Nucleare, Sezione di Milano, Via Celoria 16, 20133 Milano, Italy
- M.-C. Delattre
- IPNO Orsay, 91400 Orsay, France
- Zs. Dombradi
- MTA Atomki, H-4001 Debrecen, Hungary
- A. Gottardo
- Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Legnaro, I-35020 Legnaro, Italy
- T. Isobe
- RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
- I. Kojouharov
- GSI, Planckstrasse 1, D-64291 Darmstadt, Germany
- N. Kurz
- GSI, Planckstrasse 1, D-64291 Darmstadt, Germany
- I. Kuti
- MTA Atomki, H-4001 Debrecen, Hungary
- S. Lalkovski
- Department of Physics, University of Surrey, Guildford GU2 7XH, United Kingdom
- K. Matsui
- Department of Physics, The University of Tokyo, Bunkyo-ku, 113-0033 Tokyo, Japan
- B. Melon
- INFN Sezione di Firenze, I-50019 Firenze, Italy
- D. Mengoni
- Dipartimento di Fisica dell'Università degli Studi di Padova, I-35131 Padova, Italy; Istituto Nazionale di Fisica Nucleare, Sezione di Padova, I-35131 Padova, Italy
- T. Miyazaki
- Department of Physics, The University of Tokyo, Bunkyo-ku, 113-0033 Tokyo, Japan
- V. Modamio-Hoybjor
- Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Legnaro, I-35020 Legnaro, Italy
- S. Momiyama
- Department of Physics, The University of Tokyo, Bunkyo-ku, 113-0033 Tokyo, Japan
- D.R. Napoli
- Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Legnaro, I-35020 Legnaro, Italy
- M. Niikura
- Department of Physics, The University of Tokyo, Bunkyo-ku, 113-0033 Tokyo, Japan
- R. Orlandi
- Instituut voor Kern- en Stralingsfysica, Katholieke Universiteit Leuven, B-3001 Leuven, Belgium; Advanced Science Research Center, JAEA, Tokai, Ibaraki 319-1195, Japan
- Zs. Podolyák
- Department of Physics, University of Surrey, Guildford GU2 7XH, United Kingdom
- P.H. Regan
- Department of Physics, University of Surrey, Guildford GU2 7XH, United Kingdom; Nuclear Metrology Group, National Physical Laboratory, Teddington, Middlesex, TW11 0LW, United Kingdom
- H. Sakurai
- RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan; Department of Physics, The University of Tokyo, Bunkyo-ku, 113-0033 Tokyo, Japan
- E. Sahin
- Department of Physics, University of Oslo, N-0316 Oslo, Norway
- D. Sohler
- MTA Atomki, H-4001 Debrecen, Hungary
- H. Schaffner
- GSI, Planckstrasse 1, D-64291 Darmstadt, Germany
- R. Taniuchi
- Department of Physics, The University of Tokyo, Bunkyo-ku, 113-0033 Tokyo, Japan
- J. Taprogge
- Instituto de Estructura de la Materia, CSIC, E-28006 Madrid, Spain; Departamento de Física teórica, Universidad Autónoma de Madrid, E-28049 Madrid, Spain
- Zs. Vajta
- MTA Atomki, H-4001 Debrecen, Hungary
- O. Wieland
- Istituto Nazionale di Fisica Nucleare, Sezione di Milano, Via Celoria 16, 20133 Milano, Italy
- M. Yalcinkaya
- Department of Physics, Istanbul University, 34134 Istanbul, Turkey
- Journal volume & issue
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Vol. 781
pp. 706 – 712
Abstract
The low-lying structures of the midshell νg9/2 Ni isotopes 72Ni and 74Ni have been investigated at the RIBF facility in RIKEN within the EURICA collaboration. Previously unobserved low-lying states were accessed for the first time following β decay of the mother nuclei 72Co and 74Co. As a result, we provide a complete picture in terms of the seniority scheme up to the first (8+) levels for both nuclei. The experimental results are compared to shell-model calculations in order to define to what extent the seniority quantum number is preserved in the first neutron g9/2 shell. We find that the disappearance of the seniority isomerism in the (81+) states can be explained by a lowering of the seniority-four (6+) levels as predicted years ago. For 74Ni, the internal de-excitation pattern of the newly observed (62+) state supports a restoration of the normal seniority ordering up to spin J=4. This property, unexplained by the shell-model calculations, is in agreement with a dominance of the single-particle spherical regime near 78Ni.
