1
|
Cubiss JG, Andreyev AN, Barzakh AE, Van Duppen P, Hilaire S, Péru S, Goriely S, Al Monthery M, Althubiti NA, Andel B, Antalic S, Atanasov D, Blaum K, Cocolios TE, Day Goodacre T, de Roubin A, Farooq-Smith GJ, Fedorov DV, Fedosseev VN, Fink DA, Gaffney LP, Ghys L, Harding RD, Huyse M, Imai N, Joss DT, Kreim S, Lunney D, Lynch KM, Manea V, Marsh BA, Martinez Palenzuela Y, Molkanov PL, Neidherr D, O'Neill GG, Page RD, Prosnyak SD, Rosenbusch M, Rossel RE, Rothe S, Schweikhard L, Seliverstov MD, Sels S, Skripnikov LV, Stott A, Van Beveren C, Verstraelen E, Welker A, Wienholtz F, Wolf RN, Zuber K. Deformation versus Sphericity in the Ground States of the Lightest Gold Isotopes. PHYSICAL REVIEW LETTERS 2023; 131:202501. [PMID: 38039485 DOI: 10.1103/physrevlett.131.202501] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Revised: 08/02/2023] [Accepted: 09/18/2023] [Indexed: 12/03/2023]
Abstract
The changes in mean-squared charge radii of neutron-deficient gold nuclei have been determined using the in-source, resonance-ionization laser spectroscopy technique, at the ISOLDE facility (CERN). From these new data, nuclear deformations are inferred, revealing a competition between deformed and spherical configurations. The isotopes ^{180,181,182}Au are observed to possess well-deformed ground states and, when moving to lighter masses, a sudden transition to near-spherical shapes is seen in the extremely neutron-deficient nuclides, ^{176,177,179}Au. A case of shape coexistence and shape staggering is identified in ^{178}Au which has a ground and isomeric state with different deformations. These new data reveal a pattern in ground-state deformation unique to the gold isotopes, whereby, when moving from the heavy to light masses, a plateau of well-deformed isotopes exists around the neutron midshell, flanked by near-spherical shapes in the heavier and lighter isotopes-a trend hitherto unseen elsewhere in the nuclear chart. The experimental charge radii are compared to those from Hartree-Fock-Bogoliubov calculations using the D1M Gogny interaction and configuration mixing between states of different deformation. The calculations are constrained by the known spins, parities, and magnetic moments of the ground states in gold nuclei and show a good agreement with the experimental results.
Collapse
Affiliation(s)
- J G Cubiss
- School of Physics, Engineering and Technology, University of York, York, YO10 5DD, United Kingdom
| | - A N Andreyev
- School of Physics, Engineering and Technology, University of York, York, YO10 5DD, United Kingdom
- Advanced Science Research Center (ASRC), Japan Atomic Energy Agency, Tokai-mura, Japan
| | - A E Barzakh
- Affiliated with an institute covered by a cooperation agreement with CERN
| | - P Van Duppen
- KU Leuven, Instituut voor Kern- en Stralingsfysica, 3001 Leuven, Belgium
| | - S Hilaire
- Université Paris-Saclay, CEA, LMCE, 91680, Bruyères-le-Châtel, France
| | - S Péru
- Université Paris-Saclay, CEA, LMCE, 91680, Bruyères-le-Châtel, France
| | - S Goriely
- Institut d'Astronomie et d'Astrophysique, CP-226, Université Libre de Bruxelles, 1050 Brussels, Belgium
| | - M Al Monthery
- School of Physics, Engineering and Technology, University of York, York, YO10 5DD, United Kingdom
| | - N A Althubiti
- The University of Manchester, Department of Physics and Astronomy, Oxford Road, M13 9PL Manchester, United Kingdom
- Physics Department, College of Science, Jouf University, Sakakah, Kingdom of Saudi Arabia
| | - B Andel
- Department of Nuclear Physics and Biophysics, Comenius University in Bratislava, 84248 Bratislava, Slovakia
| | - S Antalic
- Department of Nuclear Physics and Biophysics, Comenius University in Bratislava, 84248 Bratislava, Slovakia
| | - D Atanasov
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany
- CERN, 1211, Geneva 23, Switzerland
| | - K Blaum
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany
| | - T E Cocolios
- KU Leuven, Instituut voor Kern- en Stralingsfysica, 3001 Leuven, Belgium
- The University of Manchester, Department of Physics and Astronomy, Oxford Road, M13 9PL Manchester, United Kingdom
| | - T Day Goodacre
- The University of Manchester, Department of Physics and Astronomy, Oxford Road, M13 9PL Manchester, United Kingdom
- CERN, 1211, Geneva 23, Switzerland
| | - A de Roubin
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany
| | - G J Farooq-Smith
- KU Leuven, Instituut voor Kern- en Stralingsfysica, 3001 Leuven, Belgium
- The University of Manchester, Department of Physics and Astronomy, Oxford Road, M13 9PL Manchester, United Kingdom
| | - D V Fedorov
- Affiliated with an institute covered by a cooperation agreement with CERN
| | | | - D A Fink
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany
- CERN, 1211, Geneva 23, Switzerland
| | - L P Gaffney
- KU Leuven, Instituut voor Kern- en Stralingsfysica, 3001 Leuven, Belgium
- CERN, 1211, Geneva 23, Switzerland
| | - L Ghys
- KU Leuven, Instituut voor Kern- en Stralingsfysica, 3001 Leuven, Belgium
| | - R D Harding
- School of Physics, Engineering and Technology, University of York, York, YO10 5DD, United Kingdom
- CERN, 1211, Geneva 23, Switzerland
| | - M Huyse
- KU Leuven, Instituut voor Kern- en Stralingsfysica, 3001 Leuven, Belgium
| | - N Imai
- Center for Nuclear Study (CNS), Graduate School of Science The University of Tokyo, Japan
| | - D T Joss
- Department of Physics, University of Liverpool, Liverpool, L69 7ZE, United Kingdom
| | - S Kreim
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany
- CERN, 1211, Geneva 23, Switzerland
| | - D Lunney
- CSNSM-CNRS, Université de Paris Sud, 91400 Orsay, France
| | - K M Lynch
- The University of Manchester, Department of Physics and Astronomy, Oxford Road, M13 9PL Manchester, United Kingdom
- CERN, 1211, Geneva 23, Switzerland
| | - V Manea
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany
| | | | - Y Martinez Palenzuela
- KU Leuven, Instituut voor Kern- en Stralingsfysica, 3001 Leuven, Belgium
- CERN, 1211, Geneva 23, Switzerland
| | - P L Molkanov
- Affiliated with an institute covered by a cooperation agreement with CERN
| | - D Neidherr
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, Darmstadt 64291, Germany
| | - G G O'Neill
- Department of Physics, University of Liverpool, Liverpool, L69 7ZE, United Kingdom
| | - R D Page
- Department of Physics, University of Liverpool, Liverpool, L69 7ZE, United Kingdom
| | - S D Prosnyak
- Affiliated with an institute covered by a cooperation agreement with CERN
| | - M Rosenbusch
- Institut für Physik, Universität Greifswald, 17487 Greifswald, Germany
| | - R E Rossel
- CERN, 1211, Geneva 23, Switzerland
- Institut für Physik, Johannes Gutenberg-Universität Mainz, Mainz, D-55128, Germany
| | - S Rothe
- CERN, 1211, Geneva 23, Switzerland
- Institut für Physik, Johannes Gutenberg-Universität Mainz, Mainz, D-55128, Germany
| | - L Schweikhard
- Institut für Physik, Universität Greifswald, 17487 Greifswald, Germany
| | - M D Seliverstov
- Affiliated with an institute covered by a cooperation agreement with CERN
| | - S Sels
- KU Leuven, Instituut voor Kern- en Stralingsfysica, 3001 Leuven, Belgium
| | - L V Skripnikov
- Affiliated with an institute covered by a cooperation agreement with CERN
| | - A Stott
- School of Physics, Engineering and Technology, University of York, York, YO10 5DD, United Kingdom
| | - C Van Beveren
- KU Leuven, Instituut voor Kern- en Stralingsfysica, 3001 Leuven, Belgium
| | - E Verstraelen
- KU Leuven, Instituut voor Kern- en Stralingsfysica, 3001 Leuven, Belgium
| | - A Welker
- CERN, 1211, Geneva 23, Switzerland
- Institut für Kern- und Teilchenphysik, Technische Universität Dresden, Dresden 01069, Germany
| | - F Wienholtz
- CERN, 1211, Geneva 23, Switzerland
- Institut für Physik, Universität Greifswald, 17487 Greifswald, Germany
| | - R N Wolf
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany
- Institut für Physik, Universität Greifswald, 17487 Greifswald, Germany
| | - K Zuber
- Institut für Kern- und Teilchenphysik, Technische Universität Dresden, Dresden 01069, Germany
| |
Collapse
|
2
|
Martinou A. A mechanism for shape coexistence. EPJ WEB OF CONFERENCES 2021. [DOI: 10.1051/epjconf/202125202005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The phenomenon of shape coexistence in a nucleus is about the occurence of two different nuclear states with drastically different shapes, lying close in energy. It is commonly seen in the data, that such coexisting states manifest in specific nuclei, which lie within certain islands on the nuclear chart, the islands of shape coexistence. A recently introduced mechanism predicts that these islands derive from the coexistence of two different types of magic numbers: the harmonic oscillator and the spin-orbit like. The algebraic realization of the nuclear Shell Model, the Elliott SU(3) symmetry, along with its extension, the proxy-SU(3) symmetry , are used for the parameter-free theoretical predictions of the islands of shape coexistence
Collapse
|
3
|
Bagchi S, Kanungo R, Tanaka YK, Geissel H, Doornenbal P, Horiuchi W, Hagen G, Suzuki T, Tsunoda N, Ahn DS, Baba H, Behr K, Browne F, Chen S, Cortés ML, Estradé A, Fukuda N, Holl M, Itahashi K, Iwasa N, Jansen GR, Jiang WG, Kaur S, Macchiavelli AO, Matsumoto SY, Momiyama S, Murray I, Nakamura T, Novario SJ, Ong HJ, Otsuka T, Papenbrock T, Paschalis S, Prochazka A, Scheidenberger C, Schrock P, Shimizu Y, Steppenbeck D, Sakurai H, Suzuki D, Suzuki H, Takechi M, Takeda H, Takeuchi S, Taniuchi R, Wimmer K, Yoshida K. Two-Neutron Halo is Unveiled in ^{29}F. PHYSICAL REVIEW LETTERS 2020; 124:222504. [PMID: 32567915 DOI: 10.1103/physrevlett.124.222504] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Revised: 04/17/2020] [Accepted: 05/08/2020] [Indexed: 06/11/2023]
Abstract
We report the measurement of reaction cross sections (σ_{R}^{ex}) of ^{27,29}F with a carbon target at RIKEN. The unexpectedly large σ_{R}^{ex} and derived matter radius identify ^{29}F as the heaviest two-neutron Borromean halo to date. The halo is attributed to neutrons occupying the 2p_{3/2} orbital, thereby vanishing the shell closure associated with the neutron number N=20. The results are explained by state-of-the-art shell model calculations. Coupled-cluster computations based on effective field theories of the strong nuclear force describe the matter radius of ^{27}F but are challenged for ^{29}F.
Collapse
Affiliation(s)
- S Bagchi
- Astronomy and Physics Department, Saint Mary's University, Halifax, Nova Scotia B3H 3C3, Canada
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, D-64291 Darmstadt, Germany
- Justus-Liebig University, 35392 Giessen, Germany
| | - R Kanungo
- Astronomy and Physics Department, Saint Mary's University, Halifax, Nova Scotia B3H 3C3, Canada
- TRIUMF, Vancouver, British Columbia V6T 2A3, Canada
| | - Y K Tanaka
- Astronomy and Physics Department, Saint Mary's University, Halifax, Nova Scotia B3H 3C3, Canada
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, D-64291 Darmstadt, Germany
- Justus-Liebig University, 35392 Giessen, Germany
| | - H Geissel
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, D-64291 Darmstadt, Germany
- Justus-Liebig University, 35392 Giessen, Germany
| | - P Doornenbal
- RIKEN Nishina Center, Wako, Saitama 351-0198, Japan
| | - W Horiuchi
- Department of Physics, Hokkaido University, Sapporo 060-0810, Japan
| | - G Hagen
- Physics Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
- Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996, USA
| | - T Suzuki
- Department of Physics, Nihon University, Setagaya-ku, Tokyo 156-8550, Japan
| | - N Tsunoda
- Center for Nuclear Study, University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - D S Ahn
- RIKEN Nishina Center, Wako, Saitama 351-0198, Japan
| | - H Baba
- RIKEN Nishina Center, Wako, Saitama 351-0198, Japan
| | - K Behr
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, D-64291 Darmstadt, Germany
| | - F Browne
- RIKEN Nishina Center, Wako, Saitama 351-0198, Japan
| | - S Chen
- RIKEN Nishina Center, Wako, Saitama 351-0198, Japan
| | - M L Cortés
- RIKEN Nishina Center, Wako, Saitama 351-0198, Japan
| | - A Estradé
- Department of Physics, Central Michigan University, Mount Pleasant, Michigan 48859, USA
| | - N Fukuda
- RIKEN Nishina Center, Wako, Saitama 351-0198, Japan
| | - M Holl
- Astronomy and Physics Department, Saint Mary's University, Halifax, Nova Scotia B3H 3C3, Canada
- TRIUMF, Vancouver, British Columbia V6T 2A3, Canada
| | - K Itahashi
- RIKEN Nishina Center, Wako, Saitama 351-0198, Japan
| | - N Iwasa
- Department of Physics, Tohoku University, Miyagi 980-8577, Japan
| | - G R Jansen
- Physics Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
- National Center for Computational Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - W G Jiang
- Physics Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
- Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996, USA
| | - S Kaur
- Astronomy and Physics Department, Saint Mary's University, Halifax, Nova Scotia B3H 3C3, Canada
- Department of Physics and Atmospheric Science, Dalhousie University, Halifax, Nova Scotia B3H 4R2, Canada
| | - A O Macchiavelli
- Nuclear Science Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - S Y Matsumoto
- Department of Physics, Kyoto University, Kyoto 606-8502, Japan
| | - S Momiyama
- Department of Physics, University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - I Murray
- RIKEN Nishina Center, Wako, Saitama 351-0198, Japan
- Institut de Physique Nucleaire, IN2P3, CNRS, Université Paris-Sud, Université Paris-Saclay, 91406 Orsay Cedex, France
| | - T Nakamura
- Department of Physics, Tokyo Institute of Technology, 2-12-1 O-Okayama, Meguro, Tokyo 152-8551, Japan
| | - S J Novario
- Physics Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
- Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996, USA
| | - H J Ong
- RCNP, Osaka University, Mihogaoka, Ibaraki, Osaka 567 0047, Japan
| | - T Otsuka
- RIKEN Nishina Center, Wako, Saitama 351-0198, Japan
- Department of Physics, University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - T Papenbrock
- Physics Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
- Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996, USA
| | - S Paschalis
- Department of Physics, University of York, Heslington, York YO10 5DD, United Kingdom
| | - A Prochazka
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, D-64291 Darmstadt, Germany
| | - C Scheidenberger
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, D-64291 Darmstadt, Germany
- Justus-Liebig University, 35392 Giessen, Germany
| | - P Schrock
- Center for Nuclear Study, University of Tokyo, RIKEN Campus, Wako, Saitama 351-0198, Japan
| | - Y Shimizu
- RIKEN Nishina Center, Wako, Saitama 351-0198, Japan
| | - D Steppenbeck
- RIKEN Nishina Center, Wako, Saitama 351-0198, Japan
- Center for Nuclear Study, University of Tokyo, RIKEN Campus, Wako, Saitama 351-0198, Japan
| | - H Sakurai
- RIKEN Nishina Center, Wako, Saitama 351-0198, Japan
- Department of Physics, University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - D Suzuki
- RIKEN Nishina Center, Wako, Saitama 351-0198, Japan
| | - H Suzuki
- RIKEN Nishina Center, Wako, Saitama 351-0198, Japan
| | - M Takechi
- Graduate School of Science and Technology, Niigata University, Niigata 950-2102, Japan
| | - H Takeda
- RIKEN Nishina Center, Wako, Saitama 351-0198, Japan
| | - S Takeuchi
- Department of Physics, Tokyo Institute of Technology, 2-12-1 O-Okayama, Meguro, Tokyo 152-8551, Japan
| | - R Taniuchi
- Department of Physics, University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
- Department of Physics, University of York, Heslington, York YO10 5DD, United Kingdom
| | - K Wimmer
- Department of Physics, University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - K Yoshida
- RIKEN Nishina Center, Wako, Saitama 351-0198, Japan
| |
Collapse
|
4
|
Szunyogh D, McFadden RML, Karner VL, Chatzichristos A, Day Goodacre T, Dehn MH, Formenti L, Fujimoto D, Gottberg A, Kallenberg E, Kálomista I, Kiefl RF, Larsen FH, Lassen J, Levy CDP, Li R, MacFarlane WA, McKenzie I, Morris GD, Pallada S, Pearson MR, Sauer SPA, Schaffer P, Thulstrup PW, Hemmingsen L, Stachura M. Direct observation of Mg 2+ complexes in ionic liquid solutions by 31Mg β-NMR spectroscopy. Dalton Trans 2018; 47:14431-14435. [PMID: 30280170 DOI: 10.1039/c8dt02350f] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
NMR spectra of Mg2+ ions in ionic liquids were recorded using a highly sensitive variant of NMR spectroscopy known as β-NMR. The β-NMR spectra of MgCl2 in EMIM-Ac and EMIM-DCA compare favourably with conventional NMR, and exhibit linewidths of ∼3 ppm, allowing for discrimination of species with oxygen and nitrogen coordination.
Collapse
Affiliation(s)
- Daniel Szunyogh
- Department of Chemistry, University of Copenhagen, Universitetsparken 5, 2100 København Ø, Denmark.
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
5
|
Garcia Ruiz RF, Bissell M, Gottberg A, Stachura M, Hemmingsen L, Neyens G, Severijns N. Perspectives for the VITO beam line at ISOLDE, CERN. EPJ WEB OF CONFERENCES 2015. [DOI: 10.1051/epjconf/20159307004] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
|
6
|
Gottberg A, Stachura M, Kowalska M, Bissell ML, Arcisauskaite V, Blaum K, Helmke A, Johnston K, Kreim K, Larsen FH, Neugart R, Neyens G, Garcia Ruiz RF, Szunyogh D, Thulstrup PW, Yordanov DT, Hemmingsen L. Billion-fold enhancement in sensitivity of nuclear magnetic resonance spectroscopy for magnesium ions in solution. Chemphyschem 2014; 15:3929-32. [PMID: 25303164 DOI: 10.1002/cphc.201402619] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2014] [Indexed: 11/06/2022]
Abstract
β-nuclear magnetic resonance (NMR) spectroscopy is highly sensitive compared to conventional NMR spectroscopy, and may be applied for several elements across the periodic table. β-NMR has previously been successfully applied in the fields of nuclear and solid-state physics. In this work, β-NMR is applied, for the first time, to record an NMR spectrum for a species in solution. (31)Mg β-NMR spectra are measured for as few as 10(7) magnesium ions in ionic liquid (EMIM-Ac) within minutes, as a prototypical test case. Resonances are observed at 3882.9 and 3887.2 kHz in an external field of 0.3 T. The key achievement of the current work is to demonstrate that β-NMR is applicable for the analysis of species in solution, and thus represents a novel spectroscopic technique for use in general chemistry and potentially in biochemistry.
Collapse
|
7
|
Poves A, Nowacki F, Caurier E. The three shapes of 32Mg. EPJ WEB OF CONFERENCES 2014. [DOI: 10.1051/epjconf/20146602084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
|
8
|
Yordanov DT, Bissell ML, Blaum K, De Rydt M, Geppert C, Kowalska M, Krämer J, Kreim K, Krieger A, Lievens P, Neff T, Neugart R, Neyens G, Nörtershäuser W, Sánchez R, Vingerhoets P. Nuclear charge radii of (21-32)Mg. PHYSICAL REVIEW LETTERS 2012; 108:042504. [PMID: 22400831 DOI: 10.1103/physrevlett.108.042504] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2011] [Indexed: 05/31/2023]
Abstract
Charge radii of all magnesium isotopes in the sd shell have been measured, revealing evolution of the nuclear shape throughout two prominent regions of assumed deformation centered on (24)Mg and (32)Mg. A striking correspondence is found between the nuclear charge radius and the neutron shell structure. The importance of cluster configurations towards N=8 and collectivity near N=20 is discussed in the framework of the fermionic molecular dynamics model. These essential results have been made possible by the first application of laser-induced nuclear orientation for isotope shift measurements.
Collapse
Affiliation(s)
- D T Yordanov
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, D-69117 Heidelberg, Germany.
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
9
|
Wimmer K, Kröll T, Krücken R, Bildstein V, Gernhäuser R, Bastin B, Bree N, Diriken J, Van Duppen P, Huyse M, Patronis N, Vermaelen P, Voulot D, Van de Walle J, Wenander F, Fraile LM, Chapman R, Hadinia B, Orlandi R, Smith JF, Lutter R, Thirolf PG, Labiche M, Blazhev A, Kalkühler M, Reiter P, Seidlitz M, Warr N, Macchiavelli AO, Jeppesen HB, Fiori E, Georgiev G, Schrieder G, Das Gupta S, Lo Bianco G, Nardelli S, Butterworth J, Johansen J, Riisager K. Discovery of the shape coexisting 0+ state in 32 Mg by a two neutron transfer reaction. PHYSICAL REVIEW LETTERS 2010; 105:252501. [PMID: 21231582 DOI: 10.1103/physrevlett.105.252501] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2010] [Indexed: 05/30/2023]
Abstract
The "island of inversion" nucleus 32 Mg has been studied by a (t, p) two neutron transfer reaction in inverse kinematics at REX-ISOLDE. The shape coexistent excited 0+ state in 32 Mg has been identified by the characteristic angular distribution of the protons of the Δ L=0 transfer. The excitation energy of 1058 keV is much lower than predicted by any theoretical model. The low γ-ray intensity observed for the decay of this 0+ state indicates a lifetime of more than 10 ns. Deduced spectroscopic amplitudes are compared with occupation numbers from shell-model calculations.
Collapse
Affiliation(s)
- K Wimmer
- Physik Department E12, Technische Universität München, 85748 Garching, Germany
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
10
|
Catford WN, Timis CN, Lemmon RC, Labiche M, Orr NA, Fernández-Domínguez B, Chapman R, Freer M, Chartier M, Savajols H, Rejmund M, Achouri NL, Amzal N, Ashwood NI, Baldwin TD, Burns M, Caballero L, Casadjian JM, Curtis N, de France G, Gelletly W, Liang X, Pain SD, Pucknell VPE, Rubio B, Sorlin O, Spohr K, Theisen C, Warner DD. Migration of nuclear shell gaps studied in the d(24Ne,pγ)25Ne reaction. PHYSICAL REVIEW LETTERS 2010; 104:192501. [PMID: 20866960 DOI: 10.1103/physrevlett.104.192501] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2009] [Indexed: 05/29/2023]
Abstract
The transfer of neutrons onto 24Ne has been measured using a reaccelerated radioactive beam of 24Ne to study the (d,p) reaction in inverse kinematics. The unusual raising of the first 3/2+ level in 25Ne and its significance in terms of the migration of the neutron magic number from N=20 to N=16 is put on a firm footing by confirmation of this state's identity. The raised 3/2+ level is observed simultaneously with the intruder negative parity 7/2- and 3/2- levels, providing evidence for the reduction in the N=20 gap. The coincident gamma-ray decays allowed the assignment of spins as well as the transferred orbital angular momentum. The excitation energy of the 3/2+ state shows that the established USD shell model breaks down well within the sd model space and requires a revised treatment of the proton-neutron monopole interaction.
Collapse
Affiliation(s)
- W N Catford
- Department of Physics, University of Surrey, Guildford GU2 5XH, United Kingdom
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
11
|
Yordanov DT, Blaum K, De Rydt M, Kowalska M, Neugart R, Neyens G, Hamamoto I. Comment on "Intruder configurations in the A=33 isobars: 33Mg and 33Al". PHYSICAL REVIEW LETTERS 2010; 104:129201-129202. [PMID: 20366572 DOI: 10.1103/physrevlett.104.129201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2009] [Revised: 10/09/2009] [Indexed: 05/29/2023]
|
12
|
Doornenbal P, Scheit H, Aoi N, Takeuchi S, Li K, Takeshita E, Wang H, Baba H, Deguchi S, Fukuda N, Geissel H, Gernhäuser R, Gibelin J, Hachiuma I, Hara Y, Hinke C, Inabe N, Itahashi K, Itoh S, Kameda D, Kanno S, Kawada Y, Kobayashi N, Kondo Y, Krücken R, Kubo T, Kuboki T, Kusaka K, Lantz M, Michimasa S, Motobayashi T, Nakamura T, Nakao T, Namihira K, Nishimura S, Ohnishi T, Ohtake M, Orr NA, Otsu H, Ozeki K, Satou Y, Shimoura S, Sumikama T, Takechi M, Takeda H, Tanaka KN, Tanaka K, Togano Y, Winkler M, Yanagisawa Y, Yoneda K, Yoshida A, Yoshida K, Sakurai H. Spectroscopy of 32Ne and the "Island of Inversion". PHYSICAL REVIEW LETTERS 2009; 103:032501. [PMID: 19659270 DOI: 10.1103/physrevlett.103.032501] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2009] [Indexed: 05/28/2023]
Abstract
We report on the first spectroscopic study of the N=22 nucleus 32Ne at the newly completed RIKEN Radioactive Ion Beam Factory. A single gamma-ray line with an energy of 722(9) keV was observed in both inelastic scattering of a 226 MeV/u 32Ne beam on a carbon target and proton removal from 33Na at 245 MeV/u. This transition is assigned to the deexcitation of the first Jpi=2+ state in 32Ne to the 0+ ground state. Interpreted through comparison with state-of-the-art shell-model calculations, the low excitation energy demonstrates that the "island of inversion" extends to at least N=22 for the Ne isotopes.
Collapse
Affiliation(s)
- P Doornenbal
- RIKEN Nishina Center, Wako, Saitama 351-0198, Japan
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
13
|
Tripathi V, Tabor SL, Mantica PF, Utsuno Y, Bender P, Cook J, Hoffman CR, Lee S, Otsuka T, Pereira J, Perry M, Pepper K, Pinter JS, Stoker J, Volya A, Weisshaar D. Intruder configurations in the A=33 isobars: 33Mg and 33Al. PHYSICAL REVIEW LETTERS 2008; 101:142504. [PMID: 18851524 DOI: 10.1103/physrevlett.101.142504] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2008] [Indexed: 05/26/2023]
Abstract
The beta decay of 33Mg (N=21) presented in this Letter reveals intruder configurations in both the parent and the daughter nucleus. The lowest excited states in the N=20 daughter nucleus, 33Al, are found to have nearly 2p-2h intruder configuration, thus extending the "island of inversion" beyond Mg. The allowed direct beta-decay branch to the 5/2{+} ground state of the daughter nucleus 33Al implies positive parity for the ground state of the parent 33Mg, contrary to an earlier suggestion of negative parity from a g-factor measurement. An admixture of 1p-1h and 3p-3h configurations is proposed for the ground state of 33Mg to explain all of the experimental observables.
Collapse
Affiliation(s)
- Vandana Tripathi
- Department of Physics, Florida State University, Tallahassee, Florida 32306, USA
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
14
|
Yordanov DT, Kowalska M, Blaum K, De Rydt M, Flanagan KT, Lievens P, Neugart R, Neyens G, Stroke HH. Spin and magnetic moment of 33Mg: evidence for a negative-parity intruder ground state. PHYSICAL REVIEW LETTERS 2007; 99:212501. [PMID: 18233211 DOI: 10.1103/physrevlett.99.212501] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2007] [Indexed: 05/25/2023]
Abstract
We report on the first determination of the nuclear ground-state spin of 33Mg, I=3/2, and its magnetic moment, mu= -0.7456(5) mu(N), by combining laser spectroscopy with nuclear magnetic resonance techniques. These values are inconsistent with an earlier suggested 1 particle-1 hole configuration and provide evidence for a 2 particle-2 hole intruder ground state with negative parity. The results are in agreement with an odd-neutron occupation of the 3/2 [321] Nilsson orbital at a large prolate deformation. The discussion emphasizes the need of further theoretical and experimental investigation of the island of inversion, a region previously thought to be well understood.
Collapse
Affiliation(s)
- D T Yordanov
- Instituut voor Kern- en Stralingsfysica, Katholieke Universiteit Leuven, B-3001 Leuven, Belgium
| | | | | | | | | | | | | | | | | |
Collapse
|
15
|
Gade A, Adrich P, Bazin D, Bowen MD, Brown BA, Campbell CM, Cook JM, Ettenauer S, Glasmacher T, Kemper KW, McDaniel S, Obertelli A, Otsuka T, Ratkiewicz A, Siwek K, Terry JR, Tostevin JA, Utsuno Y, Weisshaar D. Spectroscopy of 36Mg: interplay of normal and intruder configurations at the neutron-rich boundary of the "island of inversion". PHYSICAL REVIEW LETTERS 2007; 99:072502. [PMID: 17930889 DOI: 10.1103/physrevlett.99.072502] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2007] [Indexed: 05/25/2023]
Abstract
We report on the first spectroscopy study of the very neutron-rich nucleus (36)(12)Mg24 using the direct two-proton knockout reaction 9Be(38Si,36Mg+gamma)X at 83 MeV/nucleon. The energy of the first excited 2+ state of 36Mg, E(2+(1)=660(6) keV, was measured. The magnitude of the partial cross sections to the ground state and the 2+(1) state is indicative of strong intruder admixtures in the lowest-lying states as suggested by Monte Carlo shell-model calculations.
Collapse
Affiliation(s)
- A Gade
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, USA
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
16
|
Otsuka T, Matsuo T, Abe D. Mean field with tensor force and shell structure of exotic nuclei. PHYSICAL REVIEW LETTERS 2006; 97:162501. [PMID: 17155390 DOI: 10.1103/physrevlett.97.162501] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2006] [Indexed: 05/12/2023]
Abstract
The tensor force is implemented into the mean-field model so that the evolution of nuclear shells can be described for exotic nuclei as well as stable ones. Besides the tensor-force part simulating the meson exchange, the model is an extension of the successful Gogny model. One of the major issues of rare-isotope beam physics is a reduced spin-orbit splitting in neutron-rich exotic nuclei. It will be shown that the effect of the tensor force on this splitting is larger than or about equal to the one due to the neutron skin. We will present predictions for stable and exotic nuclei with comparisons to conventional results and experimental data.
Collapse
Affiliation(s)
- Takaharu Otsuka
- Department of Physics, University of Tokyo, Hongo, Tokyo, Japan
| | | | | |
Collapse
|
17
|
Campbell CM, Aoi N, Bazin D, Bowen MD, Brown BA, Cook JM, Dinca DC, Gade A, Glasmacher T, Horoi M, Kanno S, Motobayashi T, Mueller WF, Sakurai H, Starosta K, Suzuki H, Takeuchi S, Terry JR, Yoneda K, Zwahlen H. Measurement of excited states in (40)Si and evidence for weakening of the N=28 shell gap. PHYSICAL REVIEW LETTERS 2006; 97:112501. [PMID: 17025880 DOI: 10.1103/physrevlett.97.112501] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2006] [Indexed: 05/12/2023]
Abstract
Excited states in (40)Si have been established by detecting gamma rays coincident with inelastic scattering and nucleon removal reactions on a liquid hydrogen target. The low excitation energy, 986(5) keV, of the 2(1)(+) state provides evidence of a weakening in the N=28 shell closure in a neutron-rich nucleus devoid of deformation-driving proton collectivity.
Collapse
Affiliation(s)
- C M Campbell
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, USA
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|