1
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Jin Y, Niu CY, Brown KW, Li ZH, Hua H, Anthony AK, Barney J, Charity RJ, Crosby J, Dell'Aquila D, Elson JM, Estee J, Ghazali M, Jhang G, Li JG, Lynch WG, Michel N, Sobotka LG, Sweany S, Teh FCE, Thomas A, Tsang CY, Tsang MB, Wang SM, Wu HY, Yuan CX, Zhu K. First Observation of the Four-Proton Unbound Nucleus ^{18}Mg. PHYSICAL REVIEW LETTERS 2021; 127:262502. [PMID: 35029460 DOI: 10.1103/physrevlett.127.262502] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 10/18/2021] [Accepted: 11/16/2021] [Indexed: 06/14/2023]
Abstract
^{18}Mg was observed, for the first time, by the invariant-mass reconstruction of ^{14}O+4p events. The ground-state decay energy and width are E_{T}=4.865(34) MeV and Γ=115(100) keV, respectively. The observed momentum correlations between the five particles are consistent with two sequential steps of prompt 2p decay passing through the ground state of ^{16}Ne. The invariant-mass spectrum also provides evidence for an excited state at an excitation energy of 1.84(14) MeV, which is likely the first excited 2^{+} state. As this energy exceeds that for the 2^{+} state in ^{20}Mg, this observation provides an argument for the demise of the N=8 shell closure in nuclei far from stability. However, in open systems this classical argument for shell strength is compromised by Thomas-Ehrman shifts.
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Affiliation(s)
- Y Jin
- School of Physics and State Key Laboratory of Nuclear Physics and Technology, Peking University, Beijing 100871, China
| | - C Y Niu
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, USA
| | - K W Brown
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, USA
- Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, USA
| | - Z H Li
- School of Physics and State Key Laboratory of Nuclear Physics and Technology, Peking University, Beijing 100871, China
| | - H Hua
- School of Physics and State Key Laboratory of Nuclear Physics and Technology, Peking University, Beijing 100871, China
| | - A K Anthony
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, USA
- Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA
| | - J Barney
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, USA
- Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA
| | - R J Charity
- Department of Chemistry, Washington University, St. Louis, Missouri 63130, USA
| | - J Crosby
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, USA
- Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA
| | - D Dell'Aquila
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, USA
| | - J M Elson
- Department of Chemistry, Washington University, St. Louis, Missouri 63130, USA
| | - J Estee
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, USA
- Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA
| | - M Ghazali
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, USA
- Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA
| | - G Jhang
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, USA
| | - J G Li
- School of Physics and State Key Laboratory of Nuclear Physics and Technology, Peking University, Beijing 100871, China
- Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China
- School of Nuclear Science and Technology, University of Chinese Academy of Sciences, Beijing 100049, China
| | - W G Lynch
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, USA
- Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA
| | - N Michel
- Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China
- School of Nuclear Science and Technology, University of Chinese Academy of Sciences, Beijing 100049, China
| | - L G Sobotka
- Department of Chemistry, Washington University, St. Louis, Missouri 63130, USA
- Department of Physics, Washington University, St. Louis, Missouri 63130, USA
| | - S Sweany
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, USA
- Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA
| | - F C E Teh
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, USA
- Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA
| | - A Thomas
- Department of Chemistry, Washington University, St. Louis, Missouri 63130, USA
| | - C Y Tsang
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, USA
- Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA
| | - M B Tsang
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, USA
- Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA
| | - S M Wang
- Institute of Modern Physics, Fudan University, Shanghai 200433, China
- FRIB Laboratory, Michigan State University, East Lansing, Michigan 48824, USA
| | - H Y Wu
- School of Physics and State Key Laboratory of Nuclear Physics and Technology, Peking University, Beijing 100871, China
| | - C X Yuan
- Sino-French Institute of Nuclear Engineering and Technology, Sun Yat-Sen University, Zhuhai 519082, China
| | - K Zhu
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, USA
- Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA
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2
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Wang SM, Nazarewicz W. Puzzling Two-Proton Decay of ^{67}Kr. PHYSICAL REVIEW LETTERS 2018; 120:212502. [PMID: 29883183 DOI: 10.1103/physrevlett.120.212502] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Revised: 04/20/2018] [Indexed: 06/08/2023]
Abstract
Ground-state two-proton (2p) radioactivity is a rare decay mode found in a few very proton-rich isotopes. The 2p decay lifetime and properties of emitted protons carry invaluable information on nuclear structure in the presence of a low-lying proton continuum. The recently measured 2p decay of ^{67}Kr turned out to be unexpectedly fast. Since ^{67}Kr is expected to be a deformed system, we investigate the impact of deformation effects on the 2p radioactivity. We apply the recently developed Gamow coupled-channel framework, which allows for a precise description of three-body systems in the presence of rotational and vibrational couplings. This is the first application of a three-body approach to a two-nucleon decay from a deformed nucleus. We show that deformation couplings significantly increase the 2p decay width of ^{67}Kr; this finding explains the puzzling experimental data. The calculated angular proton-proton correlations reflect a competition between 1p and 2p decay modes in this nucleus.
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Affiliation(s)
- S M Wang
- FRIB/NSCL Laboratory, Michigan State University, East Lansing, Michigan 48824, USA
| | - W Nazarewicz
- Department of Physics and Astronomy and FRIB Laboratory, Michigan State University, East Lansing, Michigan 48824, USA
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3
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Revel A, Marqués FM, Sorlin O, Aumann T, Caesar C, Holl M, Panin V, Vandebrouck M, Wamers F, Alvarez-Pol H, Atar L, Avdeichikov V, Beceiro-Novo S, Bemmerer D, Benlliure J, Bertulani CA, Boillos JM, Boretzky K, Borge MJG, Caamaño M, Casarejos E, Catford WN, Cederkäll J, Chartier M, Chulkov L, Cortina-Gil D, Cravo E, Crespo R, Datta Pramanik U, Díaz Fernández P, Dillmann I, Elekes Z, Enders J, Ershova O, Estradé A, Farinon F, Fraile LM, Freer M, Galaviz D, Geissel H, Gernhäuser R, Golubev P, Göbel K, Hagdahl J, Heftrich T, Heil M, Heine M, Heinz A, Henriques A, Ignatov A, Johansson HT, Jonson B, Kahlbow J, Kalantar-Nayestanaki N, Kanungo R, Kelic-Heil A, Knyazev A, Kröll T, Kurz N, Labiche M, Langer C, Le Bleis T, Lemmon R, Lindberg S, Machado J, Marganiec J, Movsesyan A, Nacher E, Najafi M, Nilsson T, Nociforo C, Paschalis S, Perea A, Petri M, Pietri S, Plag R, Reifarth R, Ribeiro G, Rigollet C, Röder M, Rossi D, Savran D, Scheit H, Simon H, Syndikus I, Taylor JT, Tengblad O, Thies R, Togano Y, Velho P, Volkov V, Wagner A, Weick H, Wheldon C, Wilson G, Winfield JS, Woods P, Yakorev D, Zhukov M, Zilges A, Zuber K. Strong Neutron Pairing in core+4n Nuclei. PHYSICAL REVIEW LETTERS 2018; 120:152504. [PMID: 29756867 DOI: 10.1103/physrevlett.120.152504] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2018] [Revised: 02/17/2018] [Indexed: 06/08/2023]
Abstract
The emission of neutron pairs from the neutron-rich N=12 isotones ^{18}C and ^{20}O has been studied by high-energy nucleon knockout from ^{19}N and ^{21}O secondary beams, populating unbound states of the two isotones up to 15 MeV above their two-neutron emission thresholds. The analysis of triple fragment-n-n correlations shows that the decay ^{19}N(-1p)^{18}C^{*}→^{16}C+n+n is clearly dominated by direct pair emission. The two-neutron correlation strength, the largest ever observed, suggests the predominance of a ^{14}C core surrounded by four valence neutrons arranged in strongly correlated pairs. On the other hand, a significant competition of a sequential branch is found in the decay ^{21}O(-1n)^{20}O^{*}→^{18}O+n+n, attributed to its formation through the knockout of a deeply bound neutron that breaks the ^{16}O core and reduces the number of pairs.
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Affiliation(s)
- A Revel
- Grand Accélérateur National d'Ions Lourds (GANIL), CEA/DRF-CNRS/IN2P3, Bvd Henri Becquerel, 14076 Caen, France
- LPC Caen, ENSICAEN, Université de Caen, CNRS/IN2P3, F-14050 CAEN Cedex, France
| | - F M Marqués
- LPC Caen, ENSICAEN, Université de Caen, CNRS/IN2P3, F-14050 CAEN Cedex, France
| | - O Sorlin
- Grand Accélérateur National d'Ions Lourds (GANIL), CEA/DRF-CNRS/IN2P3, Bvd Henri Becquerel, 14076 Caen, France
| | - T Aumann
- Institut für Kernphysik, Technische Universität Darmstadt, 64289 Darmstadt, Germany
- GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany
| | - C Caesar
- Institut für Kernphysik, Technische Universität Darmstadt, 64289 Darmstadt, Germany
- GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany
| | - M Holl
- Institut für Kernphysik, Technische Universität Darmstadt, 64289 Darmstadt, Germany
| | - V Panin
- Institut für Kernphysik, Technische Universität Darmstadt, 64289 Darmstadt, Germany
| | - M Vandebrouck
- Irfu, CEA, Université Paris-Saclay, 91191 Gif-sur-Yvette, France
| | - F Wamers
- Institut für Kernphysik, Technische Universität Darmstadt, 64289 Darmstadt, Germany
- GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany
| | - H Alvarez-Pol
- IGFAE, Instituto Galego de Física de Altas Enerxías, Universidade de Santiago de Compostela, 15782 Santiago de Compostela, Spain
| | - L Atar
- Institut für Kernphysik, Technische Universität Darmstadt, 64289 Darmstadt, Germany
| | - V Avdeichikov
- Department of Physics, Lund University, 22100 Lund, Sweden
| | - S Beceiro-Novo
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, USA
| | - D Bemmerer
- Helmholtz-Zentrum Dresden-Rossendorf, 01328, Dresden, Germany
| | - J Benlliure
- IGFAE, Instituto Galego de Física de Altas Enerxías, Universidade de Santiago de Compostela, 15782 Santiago de Compostela, Spain
| | - C A Bertulani
- Department of Physics and Astronomy, Texas A&M University-Commerce, Commerce, Texas 75429, USA
| | - J M Boillos
- IGFAE, Instituto Galego de Física de Altas Enerxías, Universidade de Santiago de Compostela, 15782 Santiago de Compostela, Spain
| | - K Boretzky
- GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany
| | - M J G Borge
- Instituto de Estructura de la Materia, CSIC, Serrano 113 bis, 28006 Madrid, Spain
| | - M Caamaño
- IGFAE, Instituto Galego de Física de Altas Enerxías, Universidade de Santiago de Compostela, 15782 Santiago de Compostela, Spain
| | | | - W N Catford
- Department of Physics, University of Surrey, Guildford GU2 7XH, United Kingdom
| | - J Cederkäll
- Department of Physics, Lund University, 22100 Lund, Sweden
| | - M Chartier
- Oliver Lodge Laboratory, University of Liverpool, Liverpool L69 7ZE, United Kingdom
| | - L Chulkov
- NRC Kurchatov Institute, Ru-123182 Moscow, Russia
- ExtreMe Matter Institute EMMI, GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291 Darmstadt, Germany
| | - D Cortina-Gil
- IGFAE, Instituto Galego de Física de Altas Enerxías, Universidade de Santiago de Compostela, 15782 Santiago de Compostela, Spain
| | - E Cravo
- Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal
| | - R Crespo
- Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa, Portugal
| | - U Datta Pramanik
- Saha Institute of Nuclear Physics, 1/AF Bidhan Nagar, Kolkata 700064, India
| | - P Díaz Fernández
- IGFAE, Instituto Galego de Física de Altas Enerxías, Universidade de Santiago de Compostela, 15782 Santiago de Compostela, Spain
| | - I Dillmann
- GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany
- II. Physikalisches Institut, Universität Gieß en, 35392 Gießen, Germany
| | - Z Elekes
- MTA Atomki, 4001 Debrecen, Hungary
| | - J Enders
- Institut für Kernphysik, Technische Universität Darmstadt, 64289 Darmstadt, Germany
| | - O Ershova
- GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany
| | - A Estradé
- School of Physics and Astronomy, University of Edinburgh, Edinburgh EH9 3JZ, United Kingdom
| | - F Farinon
- GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany
| | - L M Fraile
- Grupo de Física Nuclear y UPARCOS, Universidad Complutense de Madrid, CEI Moncloa, 28040 Madrid, Spain
| | - M Freer
- School of Physics and Astronomy, University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - D Galaviz
- Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal
- Laboratório de Instrumentação e Física Experimental de Partículas-LIP, 1000-149 Lisbon, Portugal
| | - H Geissel
- GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany
| | - R Gernhäuser
- Physik Department E12, Technische Universität München, 85748 Garching, Germany
| | - P Golubev
- Department of Physics, Lund University, 22100 Lund, Sweden
| | - K Göbel
- Goethe-Universität Frankfurt am Main, 60438 Frankfurt am Main, Germany
| | - J Hagdahl
- Institutionen för Fysik, Chalmers Tekniska Högskola, 412 96 Göteborg, Sweden
| | - T Heftrich
- Goethe-Universität Frankfurt am Main, 60438 Frankfurt am Main, Germany
| | - M Heil
- GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany
| | - M Heine
- IPHC-CNRS/Université de Strasbourg, 67037 Strasbourg, France
| | - A Heinz
- Institutionen för Fysik, Chalmers Tekniska Högskola, 412 96 Göteborg, Sweden
| | - A Henriques
- Laboratório de Instrumentação e Física Experimental de Partículas-LIP, 1000-149 Lisbon, Portugal
| | - A Ignatov
- Institut für Kernphysik, Technische Universität Darmstadt, 64289 Darmstadt, Germany
| | - H T Johansson
- Institutionen för Fysik, Chalmers Tekniska Högskola, 412 96 Göteborg, Sweden
| | - B Jonson
- Institutionen för Fysik, Chalmers Tekniska Högskola, 412 96 Göteborg, Sweden
| | - J Kahlbow
- Institut für Kernphysik, Technische Universität Darmstadt, 64289 Darmstadt, Germany
| | | | - R Kanungo
- Astronomy and Physics Department, Saint Mary's University, Halifax, Nova Scotia B3H 3C3, Canada
| | - A Kelic-Heil
- GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany
| | - A Knyazev
- Department of Physics, Lund University, 22100 Lund, Sweden
| | - T Kröll
- Institut für Kernphysik, Technische Universität Darmstadt, 64289 Darmstadt, Germany
| | - N Kurz
- GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany
| | - M Labiche
- STFC Daresbury Laboratory, WA4 4AD Warrington, United Kingdom
| | - C Langer
- Goethe-Universität Frankfurt am Main, 60438 Frankfurt am Main, Germany
| | - T Le Bleis
- Physik Department E12, Technische Universität München, 85748 Garching, Germany
| | - R Lemmon
- STFC Daresbury Laboratory, WA4 4AD Warrington, United Kingdom
| | - S Lindberg
- Institutionen för Fysik, Chalmers Tekniska Högskola, 412 96 Göteborg, Sweden
| | - J Machado
- Laboratório de Instrumentação, Engenharia Biomédica e Física da Radiação (LIBPhysUNL), Departamento de Física, Faculdade de Ciências e Tecnologias, Universidade Nova de Lisboa, 2829-516 Monte da Caparica, Portugal
| | - J Marganiec
- Institut für Kernphysik, Technische Universität Darmstadt, 64289 Darmstadt, Germany
- GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany
- ExtreMe Matter Institute EMMI, GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291 Darmstadt, Germany
| | - A Movsesyan
- Institut für Kernphysik, Technische Universität Darmstadt, 64289 Darmstadt, Germany
| | - E Nacher
- Instituto de Estructura de la Materia, CSIC, Serrano 113 bis, 28006 Madrid, Spain
| | - M Najafi
- KVI-CART, University of Groningen, Zernikelaan 25, 9747 AA Groningen, The Netherlands
| | - T Nilsson
- Institutionen för Fysik, Chalmers Tekniska Högskola, 412 96 Göteborg, Sweden
| | - C Nociforo
- GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany
| | - S Paschalis
- Institut für Kernphysik, Technische Universität Darmstadt, 64289 Darmstadt, Germany
- Department of Physics, University of York, Heslington, York YO10 5DD, United Kingdom
| | - A Perea
- Instituto de Estructura de la Materia, CSIC, Serrano 113 bis, 28006 Madrid, Spain
| | - M Petri
- Institut für Kernphysik, Technische Universität Darmstadt, 64289 Darmstadt, Germany
- Department of Physics, University of York, Heslington, York YO10 5DD, United Kingdom
| | - S Pietri
- GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany
| | - R Plag
- GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany
| | - R Reifarth
- Goethe-Universität Frankfurt am Main, 60438 Frankfurt am Main, Germany
| | - G Ribeiro
- Instituto de Estructura de la Materia, CSIC, Serrano 113 bis, 28006 Madrid, Spain
| | - C Rigollet
- KVI-CART, University of Groningen, Zernikelaan 25, 9747 AA Groningen, The Netherlands
| | - M Röder
- Helmholtz-Zentrum Dresden-Rossendorf, 01328, Dresden, Germany
- Institut für Kern- und Teilchenphysik, Technische Universität Dresden, 01069 Dresden, Germany
| | - D Rossi
- GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany
| | - D Savran
- ExtreMe Matter Institute EMMI, GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291 Darmstadt, Germany
| | - H Scheit
- Institut für Kernphysik, Technische Universität Darmstadt, 64289 Darmstadt, Germany
| | - H Simon
- GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany
| | - I Syndikus
- Institut für Kernphysik, Technische Universität Darmstadt, 64289 Darmstadt, Germany
| | - J T Taylor
- Oliver Lodge Laboratory, University of Liverpool, Liverpool L69 7ZE, United Kingdom
| | - O Tengblad
- Instituto de Estructura de la Materia, CSIC, Serrano 113 bis, 28006 Madrid, Spain
| | - R Thies
- Institutionen för Fysik, Chalmers Tekniska Högskola, 412 96 Göteborg, Sweden
| | - Y Togano
- Department of Physics, Tokyo Institute of Technology, 2-12-1 O-Okayama, Meguro, Tokyo 152-8551, Japan
| | - P Velho
- Laboratório de Instrumentação e Física Experimental de Partículas-LIP, 1000-149 Lisbon, Portugal
| | - V Volkov
- NRC Kurchatov Institute, Ru-123182 Moscow, Russia
| | - A Wagner
- Helmholtz-Zentrum Dresden-Rossendorf, 01328, Dresden, Germany
| | - H Weick
- GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany
| | - C Wheldon
- School of Physics and Astronomy, University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - G Wilson
- Department of Physics, University of Surrey, Guildford GU2 7XH, United Kingdom
| | - J S Winfield
- GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany
| | - P Woods
- School of Physics and Astronomy, University of Edinburgh, Edinburgh EH9 3JZ, United Kingdom
| | - D Yakorev
- Helmholtz-Zentrum Dresden-Rossendorf, 01328, Dresden, Germany
| | - M Zhukov
- Institutionen för Fysik, Chalmers Tekniska Högskola, 412 96 Göteborg, Sweden
| | - A Zilges
- Institut für Kernphysik, Universität zu Köln, 50937 Köln, Germany
| | - K Zuber
- Institut für Kern- und Teilchenphysik, Technische Universität Dresden, 01069 Dresden, Germany
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4
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Goigoux T, Ascher P, Blank B, Gerbaux M, Giovinazzo J, Grévy S, Kurtukian Nieto T, Magron C, Doornenbal P, Kiss GG, Nishimura S, Söderström PA, Phong VH, Wu J, Ahn DS, Fukuda N, Inabe N, Kubo T, Kubono S, Sakurai H, Shimizu Y, Sumikama T, Suzuki H, Takeda H, Agramunt J, Algora A, Guadilla V, Montaner-Piza A, Morales AI, Orrigo SEA, Rubio B, Fujita Y, Tanaka M, Gelletly W, Aguilera P, Molina F, Diel F, Lubos D, de Angelis G, Napoli D, Borcea C, Boso A, Cakirli RB, Ganioglu E, Chiba J, Nishimura D, Oikawa H, Takei Y, Yagi S, Wimmer K, de France G, Go S, Brown BA. Two-Proton Radioactivity of ^{67}Kr. PHYSICAL REVIEW LETTERS 2016; 117:162501. [PMID: 27792367 DOI: 10.1103/physrevlett.117.162501] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2016] [Indexed: 06/06/2023]
Abstract
In an experiment with the BigRIPS separator at the RIKEN Nishina Center, we observed two-proton (2p) emission from ^{67}Kr. At the same time, no evidence for 2p emission of ^{59}Ge and ^{63}Se, two other potential candidates for this exotic radioactivity, could be observed. This observation is in line with Q value predictions which pointed to ^{67}Kr as being the best new candidate among the three for two-proton radioactivity. ^{67}Kr is only the fourth 2p ground-state emitter to be observed with a half-life of the order of a few milliseconds. The decay energy was determined to be 1690(17) keV, the 2p emission branching ratio is 37(14)%, and the half-life of ^{67}Kr is 7.4(30) ms.
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Affiliation(s)
- T Goigoux
- Centre d'Études Nucléaires de Bordeaux Gradignan, Université de Bordeaux-UMR 5797 CNRS/IN2P3, Chemin du Solarium, 33175 Gradignan, France
| | - P Ascher
- Centre d'Études Nucléaires de Bordeaux Gradignan, Université de Bordeaux-UMR 5797 CNRS/IN2P3, Chemin du Solarium, 33175 Gradignan, France
| | - B Blank
- Centre d'Études Nucléaires de Bordeaux Gradignan, Université de Bordeaux-UMR 5797 CNRS/IN2P3, Chemin du Solarium, 33175 Gradignan, France
| | - M Gerbaux
- Centre d'Études Nucléaires de Bordeaux Gradignan, Université de Bordeaux-UMR 5797 CNRS/IN2P3, Chemin du Solarium, 33175 Gradignan, France
| | - J Giovinazzo
- Centre d'Études Nucléaires de Bordeaux Gradignan, Université de Bordeaux-UMR 5797 CNRS/IN2P3, Chemin du Solarium, 33175 Gradignan, France
| | - S Grévy
- Centre d'Études Nucléaires de Bordeaux Gradignan, Université de Bordeaux-UMR 5797 CNRS/IN2P3, Chemin du Solarium, 33175 Gradignan, France
| | - T Kurtukian Nieto
- Centre d'Études Nucléaires de Bordeaux Gradignan, Université de Bordeaux-UMR 5797 CNRS/IN2P3, Chemin du Solarium, 33175 Gradignan, France
| | - C Magron
- Centre d'Études Nucléaires de Bordeaux Gradignan, Université de Bordeaux-UMR 5797 CNRS/IN2P3, Chemin du Solarium, 33175 Gradignan, France
| | - P Doornenbal
- RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - G G Kiss
- RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - S Nishimura
- 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
| | - V H Phong
- RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - J Wu
- RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - D S Ahn
- RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - N Fukuda
- RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - N Inabe
- RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - T Kubo
- RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - S Kubono
- RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - H Sakurai
- RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
- Department of Physics, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Y Shimizu
- RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - T Sumikama
- RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - H Suzuki
- RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - H Takeda
- RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - J Agramunt
- Instituto de Física Corpuscular, CSIC-Universidad de Valencia, E-46071 Valencia, Spain
| | - A Algora
- Instituto de Física Corpuscular, CSIC-Universidad de Valencia, E-46071 Valencia, Spain
- Institute of Nuclear Research of the Hungarian Academy of Sciences, P.O. Box 51, H-4001 Debrecen, Hungary
| | - V Guadilla
- Instituto de Física Corpuscular, CSIC-Universidad de Valencia, E-46071 Valencia, Spain
| | - A Montaner-Piza
- Instituto de Física Corpuscular, CSIC-Universidad de Valencia, E-46071 Valencia, Spain
| | - A I Morales
- Instituto de Física Corpuscular, CSIC-Universidad de Valencia, E-46071 Valencia, Spain
| | - S E A Orrigo
- Instituto de Física Corpuscular, CSIC-Universidad de Valencia, E-46071 Valencia, Spain
| | - B Rubio
- Instituto de Física Corpuscular, CSIC-Universidad de Valencia, E-46071 Valencia, Spain
| | - Y Fujita
- Department of Physics, Osaka University, Toyonaka, Osaka 560-0043, Japan
- Research Center for Nuclear Physics, Osaka University, Ibaraki, Osaka 567-0047, Japan
| | - M Tanaka
- Department of Physics, Osaka University, Toyonaka, Osaka 560-0043, Japan
| | - W Gelletly
- Instituto de Física Corpuscular, CSIC-Universidad de Valencia, E-46071 Valencia, Spain
- Department of Physics, University of Surrey, Guildford GU2 7XH, United Kingdom
| | - P Aguilera
- Comisión Chilena de Energía Nuclear, Casilla 188-D, Amunátegui 95, Santiago Centro, Santiago, Chile
| | - F Molina
- Comisión Chilena de Energía Nuclear, Casilla 188-D, Amunátegui 95, Santiago Centro, Santiago, Chile
| | - F Diel
- Institute of Nuclear Physics, University of Cologne, D-50937 Cologne, Germany
| | - D Lubos
- Physik Department E12, Technische Universität München, D-85748 Garching, Germany
| | - G de Angelis
- Laboratori Nazionali di Legnaro dell'INFN, I-35020 Legnaro (Padova), Italy
| | - D Napoli
- Laboratori Nazionali di Legnaro dell'INFN, I-35020 Legnaro (Padova), Italy
| | - C Borcea
- National Institute for Physics and Nuclear Engineering IFIN-HH, P.O. Box MG-6, Bucharest-Magurele, Romania
| | - A Boso
- INFN Sezione di Padova and Dipartimento di Fisica, Università di Padova, I-35131 Padova, Italy
| | - R B Cakirli
- Department of Physics, Istanbul University, Istanbul 34134, Turkey
| | - E Ganioglu
- Department of Physics, Istanbul University, Istanbul 34134, Turkey
| | - J Chiba
- Department of Physics, Tokyo University of Science, Noda, Chiba 278-8510, Japan
| | - D Nishimura
- Department of Physics, Tokyo University of Science, Noda, Chiba 278-8510, Japan
| | - H Oikawa
- Department of Physics, Tokyo University of Science, Noda, Chiba 278-8510, Japan
| | - Y Takei
- Department of Physics, Tokyo University of Science, Noda, Chiba 278-8510, Japan
| | - S Yagi
- Department of Physics, Tokyo University of Science, Noda, Chiba 278-8510, Japan
| | - K Wimmer
- Department of Physics, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - G de France
- Grand Accélérateur National d'Ions Lourds, B.P. 55027, F-14076 Caen Cedex 05, France
| | - S Go
- Department of Physics and Astronomy, University of Tennessee, 401 Nielsen Physics Building, 1408 Circle Drive, Knoxville, Tennessee 37996-1200, USA
| | - B A Brown
- Department of Physics and Astronomy, and National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824-1321, USA
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5
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Lovell A, Nunes F, Thompson I. Two neutron decay of 16Be. EPJ WEB OF CONFERENCES 2016. [DOI: 10.1051/epjconf/201611306015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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6
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Charity RJ. Continuum spectroscopy of light nuclei. EPJ WEB OF CONFERENCES 2016. [DOI: 10.1051/epjconf/201611706001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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7
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Mukha I, Grigorenko LV, Xu X, Acosta L, Casarejos E, Ciemny AA, Dominik W, Duénas-Díaz J, Dunin V, Espino JM, Estradé A, Farinon F, Fomichev A, Geissel H, Golubkova TA, Gorshkov A, Janas Z, Kamiński G, Kiselev O, Knöbel R, Krupko S, Kuich M, Litvinov YA, Marquinez-Durán G, Martel I, Mazzocchi C, Nociforo C, Ordúz AK, Pfützner M, Pietri S, Pomorski M, Prochazka A, Rymzhanova S, Sánchez-Benítez AM, Scheidenberger C, Sharov P, Simon H, Sitar B, Slepnev R, Stanoiu M, Strmen P, Szarka I, Takechi M, Tanaka YK, Weick H, Winkler M, Winfield JS, Zhukov MV. Observation and Spectroscopy of New Proton-Unbound Isotopes ³⁰Ar and ²⁹Cl: An Interplay of Prompt Two-Proton and Sequential Decay. PHYSICAL REVIEW LETTERS 2015; 115:202501. [PMID: 26613434 DOI: 10.1103/physrevlett.115.202501] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2015] [Indexed: 06/05/2023]
Abstract
Previously unknown isotopes (30)Ar and (29)Cl have been identified by measurement of the trajectories of their in-flight decay products (28)S+p+p and (28)S+p, respectively. The analysis of angular correlations of the fragments provided information on decay energies and the structure of the parent states. The ground states of (30)Ar and (29)Cl were found at 2.25(-0.10)(+0.15) and 1.8±0.1 MeV above the two- and one-proton thresholds, respectively. The lowest states in (30)Ar and (29)Cl point to a violation of isobaric symmetry in the structure of these unbound nuclei. The two-proton decay has been identified in a transition region between simultaneous two-proton and sequential proton emissions from the (30)Ar ground state, which is characterized by an interplay of three-body and two-body decay mechanisms. The first hint of a fine structure of the two-proton decay of (30)Ar*(2(+)) has been obtained by detecting two decay branches into the ground and first-excited states of the (28)S fragment.
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Affiliation(s)
- I Mukha
- GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany
- National Research Centre "Kurchatov Institute," Kurchatov square 1, 123182 Moscow, Russia
| | - L V Grigorenko
- National Research Centre "Kurchatov Institute," Kurchatov square 1, 123182 Moscow, Russia
- Flerov Laboratory of Nuclear Reactions, JINR, 141980 Dubna, Russia
- National Research Nuclear University "MEPhI," 115409 Moscow, Russia
| | - X Xu
- GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany
- II.Physikalisches Institut, Justus-Liebig-Universität, 35392 Gießen, Germany
- School of Physics and Nuclear Energy Engineering, Beihang University, 100191 Beijing, China
| | - L Acosta
- INFN, Laboratori Nazionali del Sud, Via S. Sofía, 95123 Catania, Italy
- Instituto de Física, Universidad Nacional Autónoma de México, México, D.F. 01000, Mexico
| | | | - A A Ciemny
- Faculty of Physics, University of Warsaw, 02-093 Warszawa, Poland
| | - W Dominik
- Faculty of Physics, University of Warsaw, 02-093 Warszawa, Poland
| | - J Duénas-Díaz
- Department of Applied Physics, University of Huelva, 21071 Huelva, Spain
| | - V Dunin
- Veksler and Baldin Laboratory of High Energy Physics, JINR, 141980 Dubna, Russia
| | - J M Espino
- Department of Atomic, Molecular and Nuclear Physics, University of Seville, 41012 Seville, Spain
| | - A Estradé
- University of Edinburgh, EH1 1HT Edinburgh, United Kingdom
| | - F Farinon
- GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany
| | - A Fomichev
- Flerov Laboratory of Nuclear Reactions, JINR, 141980 Dubna, Russia
| | - H Geissel
- GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany
- II.Physikalisches Institut, Justus-Liebig-Universität, 35392 Gießen, Germany
| | - T A Golubkova
- Advanced Educational and Scientific Center, Moscow State University, 121357 Moscow, Russia
| | - A Gorshkov
- Flerov Laboratory of Nuclear Reactions, JINR, 141980 Dubna, Russia
| | - Z Janas
- Faculty of Physics, University of Warsaw, 02-093 Warszawa, Poland
| | - G Kamiński
- Flerov Laboratory of Nuclear Reactions, JINR, 141980 Dubna, Russia
- Institute of Nuclear Physics PAN, 31-342 Kraków, Poland
| | - O Kiselev
- GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany
| | - R Knöbel
- GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany
- II.Physikalisches Institut, Justus-Liebig-Universität, 35392 Gießen, Germany
| | - S Krupko
- Flerov Laboratory of Nuclear Reactions, JINR, 141980 Dubna, Russia
| | - M Kuich
- Faculty of Physics, University of Warsaw, 02-093 Warszawa, Poland
- Faculty of Physics, Warsaw University of Technology, 00-662 Warszawa, Poland
| | - Yu A Litvinov
- GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany
| | - G Marquinez-Durán
- Department of Applied Physics, University of Huelva, 21071 Huelva, Spain
| | - I Martel
- Department of Applied Physics, University of Huelva, 21071 Huelva, Spain
| | - C Mazzocchi
- Faculty of Physics, University of Warsaw, 02-093 Warszawa, Poland
| | - C Nociforo
- GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany
| | - A K Ordúz
- Department of Applied Physics, University of Huelva, 21071 Huelva, Spain
| | - M Pfützner
- GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany
- Faculty of Physics, University of Warsaw, 02-093 Warszawa, Poland
| | - S Pietri
- GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany
| | - M Pomorski
- Faculty of Physics, University of Warsaw, 02-093 Warszawa, Poland
| | - A Prochazka
- GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany
| | - S Rymzhanova
- Flerov Laboratory of Nuclear Reactions, JINR, 141980 Dubna, Russia
| | | | - C Scheidenberger
- GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany
- II.Physikalisches Institut, Justus-Liebig-Universität, 35392 Gießen, Germany
| | - P Sharov
- Flerov Laboratory of Nuclear Reactions, JINR, 141980 Dubna, Russia
| | - H Simon
- GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany
| | - B Sitar
- Faculty of Mathematics and Physics, Comenius University, 84248 Bratislava, Slovakia
| | - R Slepnev
- Flerov Laboratory of Nuclear Reactions, JINR, 141980 Dubna, Russia
| | - M Stanoiu
- IFIN-HH, Post Office Box MG-6, Bucharest, Romania
| | - P Strmen
- Faculty of Mathematics and Physics, Comenius University, 84248 Bratislava, Slovakia
| | - I Szarka
- Faculty of Mathematics and Physics, Comenius University, 84248 Bratislava, Slovakia
| | - M Takechi
- GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany
| | - Y K Tanaka
- GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany
- University of Tokyo, 113-0033 Tokyo, Japan
| | - H Weick
- GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany
| | - M Winkler
- GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany
| | - J S Winfield
- GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany
| | - M V Zhukov
- Fundamental Physics, Chalmers University of Technology, S-41296 Göteborg, Sweden
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8
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Brown KW, Charity RJ, Sobotka LG, Chajecki Z, Grigorenko LV, Egorova IA, Parfenova YL, Zhukov MV, Bedoor S, Buhro WW, Elson JM, Lynch WG, Manfredi J, McNeel DG, Reviol W, Shane R, Showalter RH, Tsang MB, Winkelbauer JR, Wuosmaa AH. Observation of long-range three-body coulomb effects in the decay of (16)Ne. PHYSICAL REVIEW LETTERS 2014; 113:232501. [PMID: 25526120 DOI: 10.1103/physrevlett.113.232501] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2014] [Indexed: 06/04/2023]
Abstract
The interaction of an E/A=57.6-MeV ^{17}Ne beam with a Be target is used to populate levels in ^{16}Ne following neutron knockout reactions. The decay of ^{16}Ne states into the three-body ^{14}O+p+p continuum is observed in the High Resolution Array (HiRA). For the first time for a 2p emitter, correlations between the momenta of the three decay products are measured with sufficient resolution and statistics to allow for an unambiguous demonstration of their dependence on the long-range nature of the Coulomb interaction. Contrary to previous measurements, our measured limit Γ<80 keV for the intrinsic decay width of the ground state is not in contradiction to the small values (of the order of keV) predicted theoretically.
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Affiliation(s)
- K W Brown
- Departments of Chemistry and Physics, Washington University, Saint Louis, Missouri 63130, USA
| | - R J Charity
- Departments of Chemistry and Physics, Washington University, Saint Louis, Missouri 63130, USA
| | - L G Sobotka
- Departments of Chemistry and Physics, Washington University, Saint Louis, Missouri 63130, USA
| | - Z Chajecki
- National Superconducting Cyclotron Laboratory and Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA
| | - L V Grigorenko
- Flerov Laboratory of Nuclear Reactions, JINR, RU-141980 Dubna, Russia and Russian Research Center "The Kurchatov Institute", Kurchatov square 1, RU-123182 Moscow, Russia
| | - I A Egorova
- Bogoliubov Laboratory of Theoretical Physics, JINR, RU-141980 Dubna, Russia
| | - Yu L Parfenova
- Flerov Laboratory of Nuclear Reactions, JINR, RU-141980 Dubna, Russia and Skobel'tsyn Institute of Nuclear Physics, Moscow State University, RU-119991 Moscow, Russia
| | - M V Zhukov
- Fundamental Physics, Chalmers University of Technology, S-41296 Göteborg, Sweden
| | - S Bedoor
- Department of Physics, Western Michigan University, Kalamazoo, Michigan 49008, USA
| | - W W Buhro
- National Superconducting Cyclotron Laboratory and Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA
| | - J M Elson
- Departments of Chemistry and Physics, Washington University, Saint Louis, Missouri 63130, USA
| | - W G Lynch
- National Superconducting Cyclotron Laboratory and Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA
| | - J Manfredi
- National Superconducting Cyclotron Laboratory and Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA
| | - D G McNeel
- Department of Physics, Western Michigan University, Kalamazoo, Michigan 49008, USA
| | - W Reviol
- Departments of Chemistry and Physics, Washington University, Saint Louis, Missouri 63130, USA
| | - R Shane
- National Superconducting Cyclotron Laboratory and Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA
| | - R H Showalter
- National Superconducting Cyclotron Laboratory and Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA
| | - M B Tsang
- National Superconducting Cyclotron Laboratory and Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA
| | - J R Winkelbauer
- National Superconducting Cyclotron Laboratory and Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA
| | - A H Wuosmaa
- Department of Physics, Western Michigan University, Kalamazoo, Michigan 49008, USA
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9
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Olsen E, Pfützner M, Birge N, Brown M, Nazarewicz W, Perhac A. Landscape of two-proton radioactivity. PHYSICAL REVIEW LETTERS 2013; 110:222501. [PMID: 23767715 DOI: 10.1103/physrevlett.110.222501] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2013] [Indexed: 06/02/2023]
Abstract
Ground-state two-proton (2p) radioactivity is a decay mode found in isotopes of elements with even atomic numbers located beyond the two-proton drip line. So far, this exotic process has been experimentally observed in a few light- and medium-mass nuclides with Z≤30. In this study, using state-of-the-art nuclear density functional theory, we globally analyze 2p radioactivity and for the first time identify 2p-decay candidates in elements heavier than strontium. We predict a few cases where the competition between 2p emission and α decay may be observed. In nuclei above lead, the α-decay mode is found to be dominating and no measurable candidates for the 2p radioactivity are expected.
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Affiliation(s)
- E Olsen
- Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996, USA
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10
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Kohley Z, Baumann T, Bazin D, Christian G, DeYoung PA, Finck JE, Frank N, Jones M, Lunderberg E, Luther B, Mosby S, Nagi T, Smith JK, Snyder J, Spyrou A, Thoennessen M. Study of two-neutron radioactivity in the decay of 26O. PHYSICAL REVIEW LETTERS 2013; 110:152501. [PMID: 25167255 DOI: 10.1103/physrevlett.110.152501] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2012] [Indexed: 06/03/2023]
Abstract
A new technique was developed to measure the lifetimes of neutron unbound nuclei in the picosecond range. The decay of 26O→24O+n+n was examined as it had been predicted to have an appreciable lifetime due to the unique structure of the neutron-rich oxygen isotopes. The half-life of 26O was extracted as 4.5(-1.5)(+1.1)(stat)±3(syst) ps. This corresponds to 26O having a finite lifetime at an 82% confidence level and, thus, suggests the possibility of two-neutron radioactivity.
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Affiliation(s)
- Z Kohley
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, USA and Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, USA
| | - T Baumann
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, USA
| | - D Bazin
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, USA
| | - G Christian
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, USA and Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA
| | - P A DeYoung
- Department of Physics, Hope College, Holland, Michigan 49423, USA
| | - J E Finck
- Department of Physics, Central Michigan University, Mount Pleasant, Michigan 48859, USA
| | - N Frank
- Department of Physics and Astronomy, Augustana College, Rock Island, Illinois 61201, USA
| | - M Jones
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, USA and Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA
| | - E Lunderberg
- Department of Physics, Hope College, Holland, Michigan 49423, USA
| | - B Luther
- Department of Physics, Concordia College, Moorhead, Minnesota 56562, USA
| | - S Mosby
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, USA and Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA
| | - T Nagi
- Department of Physics, Hope College, Holland, Michigan 49423, USA
| | - J K Smith
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, USA and Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA
| | - J Snyder
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, USA and Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA
| | - A Spyrou
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, USA and Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA
| | - M Thoennessen
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, USA and Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA
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11
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Ascher P, Audirac L, Adimi N, Blank B, Borcea C, Brown BA, Companis I, Delalee F, Demonchy CE, de Oliveira Santos F, Giovinazzo J, Grévy S, Grigorenko LV, Kurtukian-Nieto T, Leblanc S, Pedroza JL, Perrot L, Pibernat J, Serani L, Srivastava PC, Thomas JC. Direct observation of two protons in the decay of 54Zn. PHYSICAL REVIEW LETTERS 2011; 107:102502. [PMID: 21981498 DOI: 10.1103/physrevlett.107.102502] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2011] [Indexed: 05/31/2023]
Abstract
The two protons emitted in the decay of 54Zn have been individually observed for the first time in a time projection chamber. The total decay energy and the half-life measured in this work agree with the results obtained in a previous experiment. Angular and energy correlations between the two protons are determined and compared to theoretical distributions of a three-body model. Within the shell model framework, the relative decay probabilities show a strong contribution of the p2 configuration for the two-proton emission. After 45Fe, the present result on 54Zn constitutes only the second case of a direct observation of the ground state two-proton decay of a long-lived isotope.
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Affiliation(s)
- P Ascher
- Centre d'Études Nucléaires de Bordeaux Gradignan-Université Bordeaux 1-UMR 5797 CNRS/IN2P3, Chemin du Solarium, BP 120, 33175 Gradignan, France
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12
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Affiliation(s)
- Bradley M. Sherrill
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, MI 48824, USA
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