1
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Charity RJ, Wylie J, Wang SM, Webb TB, Brown KW, Cerizza G, Chajecki Z, Elson JM, Estee J, Hoff DEM, Kuvin SA, Lynch WG, Manfredi J, Michel N, McNeel DG, Morfouace P, Nazarewicz W, Pruitt CD, Santamaria C, Sweany S, Smith J, Sobotka LG, Tsang MB, Wuosmaa AH. Strong Evidence for ^{9}N and the Limits of Existence of Atomic Nuclei. PHYSICAL REVIEW LETTERS 2023; 131:172501. [PMID: 37955509 DOI: 10.1103/physrevlett.131.172501] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Revised: 03/16/2023] [Accepted: 09/07/2023] [Indexed: 11/14/2023]
Abstract
The boundaries of the chart of nuclides contain exotic isotopes that possess extreme proton-to-neutron asymmetries. Here we report on strong evidence of ^{9}N, one of the most exotic proton-rich isotopes where more than one half of its constitute nucleons are unbound. With seven protons and two neutrons, this extremely proton-rich system would represent the first-known example of a ground-state five-proton emitter. The invariant-mass spectrum of its decay products can be fit with two peaks whose energies are consistent with the theoretical predictions of an open-quantum-system approach; however, we cannot rule out the possibility that only a single resonancelike peak is present in the spectrum.
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Affiliation(s)
- R J Charity
- Department of Chemistry, Washington University, St. Louis, Missouri 63130, USA
| | - J Wylie
- Facility for Rare Isotope Beams, Michigan State University, East Lansing, Michigan 48824, USA
- Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA
| | - S M Wang
- Key Laboratory of Nuclear Physics and Ion-beam Application (MOE), Institute of Modern Physics, Fudan University, Shanghai 200433, China
- Shanghai Research Center for Theoretical Nuclear Physics, NSFC and Fudan University, Shanghai 200438, China
| | - T B Webb
- Department of Physics, Washington University, St. Louis, Missouri 63130, USA
| | - K W Brown
- Facility for Rare Isotope Beams, Michigan State University, East Lansing, Michigan 48824, USA
| | - G Cerizza
- Facility for Rare Isotope Beams, Michigan State University, East Lansing, Michigan 48824, USA
| | - Z Chajecki
- Department of Physics, Western Michigan University, Kalamazoo, Michigan 49008, USA
| | - J M Elson
- Department of Chemistry, Washington University, St. Louis, Missouri 63130, USA
| | - J Estee
- Facility for Rare Isotope Beams, Michigan State University, East Lansing, Michigan 48824, USA
| | - D E M Hoff
- Department of Chemistry, Washington University, St. Louis, Missouri 63130, USA
| | - S A Kuvin
- Department of Physics, University of Connecticut, Storrs, Connecticut 06269, USA
| | - W G Lynch
- Facility for Rare Isotope Beams, Michigan State University, East Lansing, Michigan 48824, USA
- Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA
| | - J Manfredi
- Facility for Rare Isotope Beams, Michigan State University, East Lansing, Michigan 48824, USA
| | - N Michel
- Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China
| | - D G McNeel
- Department of Physics, University of Connecticut, Storrs, Connecticut 06269, USA
| | - P Morfouace
- Facility for Rare Isotope Beams, Michigan State University, East Lansing, Michigan 48824, USA
| | - W Nazarewicz
- Facility for Rare Isotope Beams, Michigan State University, East Lansing, Michigan 48824, USA
- Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA
| | - C D Pruitt
- Department of Chemistry, Washington University, St. Louis, Missouri 63130, USA
| | - C Santamaria
- Facility for Rare Isotope Beams, Michigan State University, East Lansing, Michigan 48824, USA
| | - S Sweany
- Facility for Rare Isotope Beams, Michigan State University, East Lansing, Michigan 48824, USA
| | - J Smith
- Department of Physics, University of Connecticut, Storrs, Connecticut 06269, USA
| | - L G Sobotka
- Department of Chemistry, Washington University, St. Louis, Missouri 63130, USA
- Department of Physics, Washington University, St. Louis, Missouri 63130, USA
| | - M B Tsang
- Facility for Rare Isotope Beams, Michigan State University, East Lansing, Michigan 48824, USA
| | - A H Wuosmaa
- Department of Physics, University of Connecticut, Storrs, Connecticut 06269, USA
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2
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Jones K. Reactions with a 10Be beam to study the one-neutron halo nucleus 11Be. EPJ WEB OF CONFERENCES 2016. [DOI: 10.1051/epjconf/201611301017] [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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3
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Nakamura T, Kobayashi N, Kondo Y, Satou Y, Tostevin JA, Utsuno Y, Aoi N, Baba H, Fukuda N, Gibelin J, Inabe N, Ishihara M, Kameda D, Kubo T, Motobayashi T, Ohnishi T, Orr NA, Otsu H, Otsuka T, Sakurai H, Sumikama T, Takeda H, Takeshita E, Takechi M, Takeuchi S, Togano Y, Yoneda K. Deformation-driven p-wave halos at the drip line: 31Ne. PHYSICAL REVIEW LETTERS 2014; 112:142501. [PMID: 24765946 DOI: 10.1103/physrevlett.112.142501] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2013] [Indexed: 06/03/2023]
Abstract
The halo structure of 31Ne is studied using 1n-removal reactions on C and Pb targets at 230 MeV/nucleon. A combined analysis of the cross sections of these nuclear and Coulomb dominated reactions that feed directly the 30Ne ground-state reveals 31Ne to have a small neutron separation energy, 0.15(-0.10)(+0.16) MeV, and spin-parity 3/2-. Consistency of the data with reaction and large-scale shell-model calculations identifies 31Ne as deformed and having a significant p-wave halo component, suggesting that halos are more frequent occurrences at the neutron drip line.
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Affiliation(s)
- T Nakamura
- Department of Physics, Tokyo Institute of Technology, 2-12-1 O-Okayama, Meguro, Tokyo 152-8551, Japan
| | - N Kobayashi
- Department of Physics, Tokyo Institute of Technology, 2-12-1 O-Okayama, Meguro, Tokyo 152-8551, Japan
| | - Y Kondo
- Department of Physics, Tokyo Institute of Technology, 2-12-1 O-Okayama, Meguro, Tokyo 152-8551, Japan
| | - Y Satou
- Department of Physics, Tokyo Institute of Technology, 2-12-1 O-Okayama, Meguro, Tokyo 152-8551, Japan and Department of Physics and Astronomy, Seoul National University, 599 Gwanak, Seoul 151-742, Republic of Korea
| | - J A Tostevin
- Department of Physics, University of Surrey, Guildford, Surrey, GU2 7XH, United Kingdom
| | - Y Utsuno
- Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195, Japan
| | - N Aoi
- RIKEN Nishina Center, Hirosawa 2-1, Wako, Saitama 351-0198, Japan
| | - H Baba
- RIKEN Nishina Center, Hirosawa 2-1, Wako, Saitama 351-0198, Japan
| | - N Fukuda
- RIKEN Nishina Center, Hirosawa 2-1, Wako, Saitama 351-0198, Japan
| | - J Gibelin
- LPC-ENSICAEN, IN2P3-CNRS et Université de Caen, F-14050, Caen Cedex, France
| | - N Inabe
- RIKEN Nishina Center, Hirosawa 2-1, Wako, Saitama 351-0198, Japan
| | - M Ishihara
- RIKEN Nishina Center, Hirosawa 2-1, Wako, Saitama 351-0198, Japan
| | - D Kameda
- RIKEN Nishina Center, Hirosawa 2-1, Wako, Saitama 351-0198, Japan
| | - T Kubo
- RIKEN Nishina Center, Hirosawa 2-1, Wako, Saitama 351-0198, Japan
| | - T Motobayashi
- RIKEN Nishina Center, Hirosawa 2-1, Wako, Saitama 351-0198, Japan
| | - T Ohnishi
- RIKEN Nishina Center, Hirosawa 2-1, Wako, Saitama 351-0198, Japan
| | - N A Orr
- LPC-ENSICAEN, IN2P3-CNRS et Université de Caen, F-14050, Caen Cedex, France
| | - H Otsu
- RIKEN Nishina Center, Hirosawa 2-1, Wako, Saitama 351-0198, Japan
| | - T Otsuka
- Center for Nuclear Study (CNS), the University of Tokyo, Hongo, Tokyo 113-0033, Japan
| | - H Sakurai
- RIKEN Nishina Center, Hirosawa 2-1, Wako, Saitama 351-0198, Japan
| | - T Sumikama
- Department of Physics, Tokyo University of Science, Chiba 278-8510, Japan
| | - H Takeda
- RIKEN Nishina Center, Hirosawa 2-1, Wako, Saitama 351-0198, Japan
| | - E Takeshita
- RIKEN Nishina Center, Hirosawa 2-1, Wako, Saitama 351-0198, Japan
| | - M Takechi
- RIKEN Nishina Center, Hirosawa 2-1, Wako, Saitama 351-0198, Japan
| | - S Takeuchi
- RIKEN Nishina Center, Hirosawa 2-1, Wako, Saitama 351-0198, Japan
| | - Y Togano
- Department of Physics, Tokyo Institute of Technology, 2-12-1 O-Okayama, Meguro, Tokyo 152-8551, Japan and RIKEN Nishina Center, Hirosawa 2-1, Wako, Saitama 351-0198, Japan
| | - K Yoneda
- RIKEN Nishina Center, Hirosawa 2-1, Wako, Saitama 351-0198, Japan
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4
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Schmitt KT, Jones KL, Bey A, Ahn SH, Bardayan DW, Blackmon JC, Brown SM, Chae KY, Chipps KA, Cizewski JA, Hahn KI, Kolata JJ, Kozub RL, Liang JF, Matei C, Matoš M, Matyas D, Moazen B, Nesaraja C, Nunes FM, O'Malley PD, Pain SD, Peters WA, Pittman ST, Roberts A, Shapira D, Shriner JF, Smith MS, Spassova I, Stracener DW, Villano AN, Wilson GL. Halo nucleus 11Be: a spectroscopic study via neutron transfer. PHYSICAL REVIEW LETTERS 2012; 108:192701. [PMID: 23003029 DOI: 10.1103/physrevlett.108.192701] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2012] [Indexed: 06/01/2023]
Abstract
The best examples of halo nuclei, exotic systems with a diffuse nuclear cloud surrounding a tightly bound core, are found in the light, neutron-rich region, where the halo neutrons experience only weak binding and a weak, or no, potential barrier. Modern direct-reaction measurement techniques provide powerful probes of the structure of exotic nuclei. Despite more than four decades of these studies on the benchmark one-neutron halo nucleus 11Be, the spectroscopic factors for the two bound states remain poorly constrained. In the present work, the 10Be(d,p) reaction has been used in inverse kinematics at four beam energies to study the structure of 11Be. The spectroscopic factors extracted using the adiabatic model were found to be consistent across the four measurements and were largely insensitive to the optical potential used. The extracted spectroscopic factor for a neutron in an nℓj=2s(1/2) state coupled to the ground state of 10Be is 0.71(5). For the first excited state at 0.32 MeV, a spectroscopic factor of 0.62(4) is found for the halo neutron in a 1p(1/2) state.
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Affiliation(s)
- K T Schmitt
- Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996, USA
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5
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Grinyer GF, Bazin D, Gade A, Tostevin JA, Adrich P, Bowen MD, Brown BA, Campbell CM, Cook JM, Glasmacher T, McDaniel S, Navrátil P, Obertelli A, Quaglioni S, Siwek K, Terry JR, Weisshaar D, Wiringa RB. Knockout reactions from p-shell nuclei: tests of ab initio structure models. PHYSICAL REVIEW LETTERS 2011; 106:162502. [PMID: 21599362 DOI: 10.1103/physrevlett.106.162502] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2010] [Indexed: 05/30/2023]
Abstract
Absolute cross sections have been determined following single neutron knockout reactions from 10Be and 10C at intermediate energy. Nucleon density distributions and bound-state wave function overlaps obtained from both variational Monte Carlo (VMC) and no core shell model (NCSM) ab initio calculations have been incorporated into the theoretical description of knockout reactions. Comparison to experimental cross sections demonstrates that the VMC approach, with the inclusion of 3-body forces, provides the best overall agreement while the NCSM and conventional shell-model calculations both overpredict the cross sections by 20% to 30% for 10Be and by 40% to 50% for 10C, respectively. This study gains new insight into the importance of 3-body forces and continuum effects in light nuclei and provides a sensitive technique to assess the accuracy of ab initio calculations for describing these effects.
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Affiliation(s)
- G F Grinyer
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, USA.
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6
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Alamanos N, Gillibert A. Selected Topics in Reaction Studies with Exotic Nuclei. THE EUROSCHOOL LECTURES ON PHYSICS WITH EXOTIC BEAMS, VOL. I 2004. [DOI: 10.1007/978-3-540-44490-9_9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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7
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Cortina-Gil D, Fernandez-Vazquez J, Aumann T, Baumann T, Benlliure J, Borge MJG, Chulkov LV, Datta Pramanik U, Forssén C, Fraile LM, Geissel H, Gerl J, Hammache F, Itahashi K, Janik R, Jonson B, Mandal S, Markenroth K, Meister M, Mocko M, Münzenberg G, Ohtsubo T, Ozawa A, Prezado Y, Pribora V, Riisager K, Scheit H, Schneider R, Schrieder G, Simon H, Sitar B, Stolz A, Strmen P, Sümmerer K, Szarka I, Weick H. Shell structure of the near-dripline nucleus 23O. PHYSICAL REVIEW LETTERS 2004; 93:062501. [PMID: 15323623 DOI: 10.1103/physrevlett.93.062501] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2003] [Indexed: 05/24/2023]
Abstract
Breakup reactions were used to study the ground-state configuration of the neutron-rich isotope 23O. The 22O fragments produced in one-nucleon removal from 23O at 938 MeV/nucleon in a carbon target were detected in coincidence with deexciting gamma rays. The widths of the longitudinal momentum distributions of the 22O fragments and the one-neutron removal cross sections were interpreted in the framework of a simple theoretical model which favors the assignment of Ipi = 1/2+ to the 23O ground state.
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Affiliation(s)
- D Cortina-Gil
- Universidad de Santiago de Compostela, E-15706, Spain
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8
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Navin A, Anthony DW, Aumann T, Baumann T, Bazin D, Blumenfeld Y, Brown BA, Glasmacher T, Hansen PG, Ibbotson RW, Lofy PA, Maddalena V, Miller K, Nakamura T, Pritychenko BV, Sherrill BM, Spears E, Steiner M, Tostevin JA, Yurkon J, Wagner A. Direct evidence for the breakdown of the N = 8 shell closure in 12Be. PHYSICAL REVIEW LETTERS 2000; 85:266-269. [PMID: 10991259 DOI: 10.1103/physrevlett.85.266] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/1999] [Indexed: 05/23/2023]
Abstract
Partial cross sections and corresponding momentum distributions have been studied in the one-neutron knockout reaction ( 12Be,11Be+gamma) on a 9Be target at 78 MeV/nucleon. The resulting spectroscopic factors for the only two bound states of 11Be are 0.42+/-0.06 ( 1/2(+)) and 0.37+/-0.06 ( 1/2(-)), where the errors are experimental only. This result shows that N = 8 is not a good closed shell in the neutron-rich 12Be and that the last neutron pair is two-thirds in the ( 1s(2)+0d(2)) intruder configuration.
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Affiliation(s)
- A Navin
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824 and Nuclear Physics Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085, India
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9
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Oliveira JM, Lepine-Szily A, Bohlen HG, Ostrowski AN, Lichtenthaler R, Laird AM, Lima GF, Maunoury L, Roussel-Chomaz P, Savajols H, Trinder W, Villari AC. Observation of the 11N ground state. PHYSICAL REVIEW LETTERS 2000; 84:4056-4059. [PMID: 10990609 DOI: 10.1103/physrevlett.84.4056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/1999] [Indexed: 05/23/2023]
Abstract
The ground state of the proton-rich, unbound nucleus 11N was observed, together with six excited states using the multinucleon transfer reaction 10B(14N,13B)11N at 30A MeV incident energy at Grand Accelerateur National d'Ions Lourds. Levels of 11N are observed as well defined resonances in the spectrum of the 13B ejectiles. They are localized at 1.63(5), 2.16(5), 3.06(8), 3.61(5), 4.33(5), 5.98(10), and 6.54(10) MeV above the 10C+p threshold. The ground-state resonance has a mass excess of 24.618(50) MeV; the experimental width is smaller than theoretical predictions.
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Affiliation(s)
- JM Oliveira
- IFUSP-Universidade de Sao Paulo, CP 66318, 05389-970 Sao Paulo, Brazil and CEBES-Centro de Ciencias Exatas, Biologicas e da Saude, Universidade de Sorocaba, Sorocaba, Brazil
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