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Cederwall B, Liu X, Aktas Ö, Ertoprak A, Zhang W, Qi C, Clément E, de France G, Ralet D, Gadea A, Goasduff A, Jaworski G, Kuti I, Nyakó BM, Nyberg J, Palacz M, Wadsworth R, Valiente-Dobón JJ, Al-Azri H, Ataç Nyberg A, Bäck T, de Angelis G, Doncel M, Dudouet J, Gottardo A, Jurado M, Ljungvall J, Mengoni D, Napoli DR, Petrache CM, Sohler D, Timár J, Barrientos D, Bednarczyk P, Benzoni G, Birkenbach B, Boston AJ, Boston HC, Burrows I, Charles L, Ciemala M, Crespi FCL, Cullen DM, Désesquelles P, Domingo-Pardo C, Eberth J, Erduran N, Ertürk S, González V, Goupil J, Hess H, Huyuk T, Jungclaus A, Korten W, Lemasson A, Leoni S, Maj A, Menegazzo R, Million B, Perez-Vidal RM, Podolyak Z, Pullia A, Recchia F, Reiter P, Saillant F, Salsac MD, Sanchis E, Simpson J, Stezowski O, Theisen C, Zielińska M. Isospin Properties of Nuclear Pair Correlations from the Level Structure of the Self-Conjugate Nucleus ^{88}Ru. Phys Rev Lett 2020; 124:062501. [PMID: 32109090 DOI: 10.1103/physrevlett.124.062501] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Revised: 08/27/2019] [Accepted: 12/18/2019] [Indexed: 06/10/2023]
Abstract
The low-lying energy spectrum of the extremely neutron-deficient self-conjugate (N=Z) nuclide _{44}^{88}Ru_{44} has been measured using the combination of the Advanced Gamma Tracking Array (AGATA) spectrometer, the NEDA and Neutron Wall neutron detector arrays, and the DIAMANT charged particle detector array. Excited states in ^{88}Ru were populated via the ^{54}Fe(^{36}Ar,2nγ)^{88}Ru^{*} fusion-evaporation reaction at the Grand Accélérateur National d'Ions Lourds (GANIL) accelerator complex. The observed γ-ray cascade is assigned to ^{88}Ru using clean prompt γ-γ-2-neutron coincidences in anticoincidence with the detection of charged particles, confirming and extending the previously assigned sequence of low-lying excited states. It is consistent with a moderately deformed rotating system exhibiting a band crossing at a rotational frequency that is significantly higher than standard theoretical predictions with isovector pairing, as well as observations in neighboring N>Z nuclides. The direct observation of such a "delayed" rotational alignment in a deformed N=Z nucleus is in agreement with theoretical predictions related to the presence of strong isoscalar neutron-proton pair correlations.
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Affiliation(s)
- B Cederwall
- KTH Royal Institute of Technology, 10691 Stockholm, Sweden
| | - X Liu
- KTH Royal Institute of Technology, 10691 Stockholm, Sweden
| | - Ö Aktas
- KTH Royal Institute of Technology, 10691 Stockholm, Sweden
| | - A Ertoprak
- KTH Royal Institute of Technology, 10691 Stockholm, Sweden
- Department of Physics, Faculty of Science, Istanbul University, Vezneciler/Fatih, 34134 Istanbul, Turkey
| | - W Zhang
- KTH Royal Institute of Technology, 10691 Stockholm, Sweden
| | - C Qi
- KTH Royal Institute of Technology, 10691 Stockholm, Sweden
| | - E Clément
- Grand Accélérateur National d'Ions Lourds (GANIL), CEA/DSM-CNRS/IN2P3, Bd Henri Becquerel, BP 55027, F-14076 Caen Cedex 5, France
| | - G de France
- Grand Accélérateur National d'Ions Lourds (GANIL), CEA/DSM-CNRS/IN2P3, Bd Henri Becquerel, BP 55027, F-14076 Caen Cedex 5, France
| | - D Ralet
- Centre de Sciences Nucléaires et Sciences de la Matière, CNRS/IN2P3, Université Paris-Saclay, 91405 Orsay, France
| | - A Gadea
- Instituto de Física Corpuscular, CSIC-Universidad de Valencia, E-46980 Valencia, Spain
| | - A Goasduff
- Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Legnaro, I-35020 Legnaro, Italy
| | - G Jaworski
- Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Legnaro, I-35020 Legnaro, Italy
- Heavy Ion Laboratory, University of Warsaw, ul. Pasteura 5A,02-093 Warszawa, Poland
| | - I Kuti
- MTA Atomki, H-4001 Debrecen, Hungary
| | - B M Nyakó
- MTA Atomki, H-4001 Debrecen, Hungary
| | - J Nyberg
- Department of Physics and Astronomy, Uppsala University, SE-75121 Uppsala, Sweden
| | - M Palacz
- Heavy Ion Laboratory, University of Warsaw, ul. Pasteura 5A,02-093 Warszawa, Poland
| | - R Wadsworth
- Department of Physics, University of York, Heslington, York, YO10 5DD, United Kingdom
| | - J J Valiente-Dobón
- Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Legnaro, I-35020 Legnaro, Italy
| | - H Al-Azri
- Rustaq College of Education, Department of Science, 329 Al-Rustaq, Sultanate of Oman
| | - A Ataç Nyberg
- KTH Royal Institute of Technology, 10691 Stockholm, Sweden
| | - T Bäck
- KTH Royal Institute of Technology, 10691 Stockholm, Sweden
| | - G de Angelis
- Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Legnaro, I-35020 Legnaro, Italy
| | - M Doncel
- KTH Royal Institute of Technology, 10691 Stockholm, Sweden
- Department of Physics, Oliver Lodge Laboratory, University of Liverpool, Liverpool L69 7ZE, United Kingdom
| | - J Dudouet
- Université Lyon, CNRS/IN2P3, IPN-Lyon, F-69622, Villeurbanne, France
| | - A Gottardo
- Centre de Sciences Nucléaires et Sciences de la Matière, CNRS/IN2P3, Université Paris-Saclay, 91405 Orsay, France
| | - M Jurado
- Instituto de Física Corpuscular, CSIC-Universidad de Valencia, E-46980 Valencia, Spain
| | - J Ljungvall
- Centre de Sciences Nucléaires et Sciences de la Matière, CNRS/IN2P3, Université Paris-Saclay, 91405 Orsay, France
| | - D Mengoni
- Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Legnaro, I-35020 Legnaro, Italy
| | - D R Napoli
- Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Legnaro, I-35020 Legnaro, Italy
| | - C M Petrache
- Centre de Sciences Nucléaires et Sciences de la Matière, CNRS/IN2P3, Université Paris-Saclay, 91405 Orsay, France
| | - D Sohler
- MTA Atomki, H-4001 Debrecen, Hungary
| | - J Timár
- MTA Atomki, H-4001 Debrecen, Hungary
| | | | - P Bednarczyk
- The Henryk Niewodniczański Institute of Nuclear Physics, Polish Academy of Sciences, ul. Radzikowskiego 152, 31-342 Kraków, Poland
| | - G Benzoni
- INFN Sezione di Milano, I-20133 Milano, Italy
| | - B Birkenbach
- Institut für Kernphysik, Universität zu Köln, Zülpicher Str. 77, D-50937 Köln, Germany
| | - A J Boston
- Oliver Lodge Laboratory, The University of Liverpool, Liverpool, L69 7ZE, United Kingdom
| | - H C Boston
- Oliver Lodge Laboratory, The University of Liverpool, Liverpool, L69 7ZE, United Kingdom
| | - I Burrows
- STFC Daresbury Laboratory, Daresbury, Warrington, WA4 4AD, United Kingdom
| | - L Charles
- IPHC, UNISTRA, CNRS, 23 rue du Loess, 67200 Strasbourg, France
| | - M Ciemala
- The Henryk Niewodniczański Institute of Nuclear Physics, Polish Academy of Sciences, ul. Radzikowskiego 152, 31-342 Kraków, Poland
| | - F C L Crespi
- University of Milano, Department of Physics, I-20133 Milano, Italy
- INFN Milano, I-20133 Milano, Italy
| | - D M Cullen
- Nuclear Physics Group, Schuster Laboratory, University of Manchester, Manchester, M13 9PL, United Kingdom
| | - P Désesquelles
- Centre de Sciences Nucléaires et Sciences de la Matière, CNRS/IN2P3, Université Paris-Saclay, 91405 Orsay, France
- CNRS-IN2P3, Universiteé Paris-Saclay, Bat 104, F-91405 Orsay Campus, France
| | - C Domingo-Pardo
- Instituto de Física Corpuscular, CSIC-Universidad de Valencia, E-46071 Valencia, Spain
| | - J Eberth
- Institut für Kernphysik, Universität zu Köln, Zülpicher Str. 77, D-50937 Köln, Germany
| | - N Erduran
- Faculty of Engineering and Natural Sciences, Istanbul Sabahattin Zaim University, 34303, Istanbul, Turkey
| | - S Ertürk
- Department of Physics, University of Nigde, 51240 Nigde, Turkey
| | - V González
- Departamento de Ingeniería Electrónica, Universitat de Valencia, 46100 Burjassot, Valencia, Spain
| | - J Goupil
- Grand Accélérateur National d'Ions Lourds (GANIL), CEA/DSM-CNRS/IN2P3, Bd Henri Becquerel, BP 55027, F-14076 Caen Cedex 5, France
| | - H Hess
- Institut für Kernphysik, Universität zu Köln, Zülpicher Str. 77, D-50937 Köln, Germany
| | - T Huyuk
- Instituto de Física Corpuscular, CSIC-Universidad de Valencia, E-46980 Valencia, Spain
| | - A Jungclaus
- Instituto de Estructura de la Materia, CSIC, Madrid, E-28006 Madrid, Spain
| | - W Korten
- Irfu, CEA, Université Paris-Saclay, F-91191 Gif-sur-Yvette, France
| | - A Lemasson
- Grand Accélérateur National d'Ions Lourds (GANIL), CEA/DSM-CNRS/IN2P3, Bd Henri Becquerel, BP 55027, F-14076 Caen Cedex 5, France
| | - S Leoni
- University of Milano, Department of Physics, I-20133 Milano, Italy
- INFN Milano, I-20133 Milano, Italy
| | - A Maj
- The Henryk Niewodniczański Institute of Nuclear Physics, Polish Academy of Sciences, ul. Radzikowskiego 152, 31-342 Kraków, Poland
| | | | | | - R M Perez-Vidal
- Instituto de Física Corpuscular, CSIC-Universidad de Valencia, E-46071 Valencia, Spain
| | - Zs Podolyak
- Department of Physics, University of Surrey, Guildford, GU2 7XH, United Kingdom
| | - A Pullia
- University of Milano, Department of Physics, I-20133 Milano, Italy
- INFN Milano, I-20133 Milano, Italy
| | - F Recchia
- Dipartimento di Fisica e Astronomia dell'Università di Padova and INFN Padova, I-35131 Padova, Italy
| | - P Reiter
- Institut für Kernphysik, Universität zu Köln, Zülpicher Str. 77, D-50937 Köln, Germany
| | - F Saillant
- Grand Accélérateur National d'Ions Lourds (GANIL), CEA/DSM-CNRS/IN2P3, Bd Henri Becquerel, BP 55027, F-14076 Caen Cedex 5, France
| | - M D Salsac
- Irfu, CEA, Université Paris-Saclay, F-91191 Gif-sur-Yvette, France
| | - E Sanchis
- Departamento de Ingeniería Electrónica, Universitat de Valencia, 46100 Burjassot, Valencia, Spain
| | - J Simpson
- STFC Daresbury Laboratory, Daresbury, Warrington, WA4 4AD, United Kingdom
| | - O Stezowski
- Université Lyon 1, CNRS/IN2P3, IPN-Lyon, F-69622, Villeurbanne, France
| | - Ch Theisen
- Irfu, CEA, Université Paris-Saclay, F-91191 Gif-sur-Yvette, France
| | - M Zielińska
- Irfu, CEA, Université Paris-Saclay, F-91191 Gif-sur-Yvette, France
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Cederwall B, Doncel M, Aktas Ö, Ertoprak A, Liotta R, Qi C, Grahn T, Cullen DM, Hodge D, Giles M, Stolze S, Badran H, Braunroth T, Calverley T, Cox DM, Fang YD, Greenlees PT, Hilton J, Ideguchi E, Julin R, Juutinen S, Raju MK, Li H, Liu H, Matta S, Modamio V, Pakarinen J, Papadakis P, Partanen J, Petrache CM, Rahkila P, Ruotsalainen P, Sandzelius M, Sarén J, Scholey C, Sorri J, Subramaniam P, Taylor MJ, Uusitalo J, Valiente-Dobón JJ. Lifetime Measurements of Excited States in ^{172}Pt and the Variation of Quadrupole Transition Strength with Angular Momentum. Phys Rev Lett 2018; 121:022502. [PMID: 30085703 DOI: 10.1103/physrevlett.121.022502] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2018] [Revised: 04/19/2018] [Indexed: 06/08/2023]
Abstract
Lifetimes of the first excited 2^{+} and 4^{+} states in the extremely neutron-deficient nuclide ^{172}Pt have been measured for the first time using the recoil-distance Doppler shift and recoil-decay tagging techniques. An unusually low value of the ratio B(E2:4_{1}^{+}→2_{1}^{+})/B(E2:2_{1}^{+}→0_{gs}^{+})=0.55(19) was found, similar to a handful of other such anomalous cases observed in the entire Segré chart. The observation adds to a cluster of a few extremely neutron-deficient nuclides of the heavy transition metals with neutron numbers N≈90-94 featuring the effect. No theoretical model calculations reported to date have been able to explain the anomalously low B(E2:4_{1}^{+}→2_{1}^{+})/B(E2:2_{1}^{+}→0_{gs}^{+}) ratios observed in these cases. Such low values cannot, e.g., be explained within the framework of the geometrical collective model or by algebraic approaches within the interacting boson model framework. It is proposed that the group of B(E2:4_{1}^{+}→2_{1}^{+})/B(E2:2_{1}^{+}→0_{gs}^{+}) ratios in the extremely neutron-deficient even-even W, Os, and Pt nuclei around neutron numbers N≈90-94 reveal a quantum phase transition from a seniority-conserving structure to a collective regime as a function of neutron number. Although a system governed by seniority symmetry is the only theoretical framework for which such an effect may naturally occur, the phenomenon is highly unexpected for these nuclei that are not situated near closed shells.
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Affiliation(s)
- B Cederwall
- KTH Royal Institute of Technology, 10691 Stockholm, Sweden
| | - M Doncel
- Department of Physics, Oliver Lodge Laboratory, University of Liverpool, Liverpool L69 7ZE, United Kingdom
| | - Ö Aktas
- KTH Royal Institute of Technology, 10691 Stockholm, Sweden
| | - A Ertoprak
- KTH Royal Institute of Technology, 10691 Stockholm, Sweden
- Department of Physics, Faculty of Science, Istanbul University, Vezneciler/Fatih, 34134 Istanbul, Turkey
| | - R Liotta
- KTH Royal Institute of Technology, 10691 Stockholm, Sweden
| | - C Qi
- KTH Royal Institute of Technology, 10691 Stockholm, Sweden
| | - T Grahn
- epartment of Physics, University of Jyvaskyla, P.O. Box 35, FI-40014 Jyväskylä, Finland
| | - D M Cullen
- Schuster Building, School of Physics and Astronomy, The University of Manchester, Manchester M13 9PL, United Kingdom
| | - D Hodge
- Schuster Building, School of Physics and Astronomy, The University of Manchester, Manchester M13 9PL, United Kingdom
| | - M Giles
- Schuster Building, School of Physics and Astronomy, The University of Manchester, Manchester M13 9PL, United Kingdom
| | - S Stolze
- epartment of Physics, University of Jyvaskyla, P.O. Box 35, FI-40014 Jyväskylä, Finland
| | - H Badran
- epartment of Physics, University of Jyvaskyla, P.O. Box 35, FI-40014 Jyväskylä, Finland
| | - T Braunroth
- Institut für Kernphysik, Universität zu Köln, 50937 Köln, Germany
| | - T Calverley
- epartment of Physics, University of Jyvaskyla, P.O. Box 35, FI-40014 Jyväskylä, Finland
| | - D M Cox
- epartment of Physics, University of Jyvaskyla, P.O. Box 35, FI-40014 Jyväskylä, Finland
| | - Y D Fang
- Research Center for Nuclear Physics, Osaka University, JP-567-0047 Osaka, Japan
| | - P T Greenlees
- epartment of Physics, University of Jyvaskyla, P.O. Box 35, FI-40014 Jyväskylä, Finland
| | - J Hilton
- epartment of Physics, University of Jyvaskyla, P.O. Box 35, FI-40014 Jyväskylä, Finland
| | - E Ideguchi
- Research Center for Nuclear Physics, Osaka University, JP-567-0047 Osaka, Japan
| | - R Julin
- epartment of Physics, University of Jyvaskyla, P.O. Box 35, FI-40014 Jyväskylä, Finland
| | - S Juutinen
- epartment of Physics, University of Jyvaskyla, P.O. Box 35, FI-40014 Jyväskylä, Finland
| | - M Kumar Raju
- Research Center for Nuclear Physics, Osaka University, JP-567-0047 Osaka, Japan
| | - H Li
- Grand Accélérateur National dâIons Lourds (GANIL), CEA/DSMâCNRS/IN2P3, F-14076 Caen Cedex 5, France
| | - H Liu
- KTH Royal Institute of Technology, 10691 Stockholm, Sweden
| | - S Matta
- KTH Royal Institute of Technology, 10691 Stockholm, Sweden
| | - V Modamio
- Department of Physics, University of Oslo, NO-0316 Oslo, Norway
| | - J Pakarinen
- epartment of Physics, University of Jyvaskyla, P.O. Box 35, FI-40014 Jyväskylä, Finland
| | - P Papadakis
- epartment of Physics, University of Jyvaskyla, P.O. Box 35, FI-40014 Jyväskylä, Finland
| | - J Partanen
- epartment of Physics, University of Jyvaskyla, P.O. Box 35, FI-40014 Jyväskylä, Finland
| | - C M Petrache
- Centre de Sciences Nucléaires et Sciences de la Matière, CNRS/IN2P3, Université Paris-Saclay, 91405 Orsay, France
| | - P Rahkila
- epartment of Physics, University of Jyvaskyla, P.O. Box 35, FI-40014 Jyväskylä, Finland
| | - P Ruotsalainen
- epartment of Physics, University of Jyvaskyla, P.O. Box 35, FI-40014 Jyväskylä, Finland
| | - M Sandzelius
- epartment of Physics, University of Jyvaskyla, P.O. Box 35, FI-40014 Jyväskylä, Finland
| | - J Sarén
- epartment of Physics, University of Jyvaskyla, P.O. Box 35, FI-40014 Jyväskylä, Finland
| | - C Scholey
- epartment of Physics, University of Jyvaskyla, P.O. Box 35, FI-40014 Jyväskylä, Finland
| | - J Sorri
- epartment of Physics, University of Jyvaskyla, P.O. Box 35, FI-40014 Jyväskylä, Finland
- Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Legnaro, I-35020 Legnaro, Italy
| | - P Subramaniam
- KTH Royal Institute of Technology, 10691 Stockholm, Sweden
| | - M J Taylor
- Division of Cancer Sciences, School of Medical Sciences, The University of Manchester, Manchester, M13 9PL, United Kingdom
| | - J Uusitalo
- epartment of Physics, University of Jyvaskyla, P.O. Box 35, FI-40014 Jyväskylä, Finland
| | - J J Valiente-Dobón
- Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Legnaro, I-35020 Legnaro, Italy
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