2
|
Kondo Y, Achouri NL, Falou HA, Atar L, Aumann T, Baba H, Boretzky K, Caesar C, Calvet D, Chae H, Chiga N, Corsi A, Delaunay F, Delbart A, Deshayes Q, Dombrádi Z, Douma CA, Ekström A, Elekes Z, Forssén C, Gašparić I, Gheller JM, Gibelin J, Gillibert A, Hagen G, Harakeh MN, Hirayama A, Hoffman CR, Holl M, Horvat A, Horváth Á, Hwang JW, Isobe T, Jiang WG, Kahlbow J, Kalantar-Nayestanaki N, Kawase S, Kim S, Kisamori K, Kobayashi T, Körper D, Koyama S, Kuti I, Lapoux V, Lindberg S, Marqués FM, Masuoka S, Mayer J, Miki K, Murakami T, Najafi M, Nakamura T, Nakano K, Nakatsuka N, Nilsson T, Obertelli A, Ogata K, de Oliveira Santos F, Orr NA, Otsu H, Otsuka T, Ozaki T, Panin V, Papenbrock T, Paschalis S, Revel A, Rossi D, Saito AT, Saito TY, Sasano M, Sato H, Satou Y, Scheit H, Schindler F, Schrock P, Shikata M, Shimizu N, Shimizu Y, Simon H, Sohler D, Sorlin O, Stuhl L, Sun ZH, Takeuchi S, Tanaka M, Thoennessen M, Törnqvist H, Togano Y, Tomai T, Tscheuschner J, Tsubota J, Tsunoda N, Uesaka T, Utsuno Y, Vernon I, Wang H, Yang Z, Yasuda M, Yoneda K, Yoshida S. First observation of 28O. Nature 2023; 620:965-970. [PMID: 37648757 PMCID: PMC10630140 DOI: 10.1038/s41586-023-06352-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Accepted: 06/21/2023] [Indexed: 09/01/2023]
Abstract
Subjecting a physical system to extreme conditions is one of the means often used to obtain a better understanding and deeper insight into its organization and structure. In the case of the atomic nucleus, one such approach is to investigate isotopes that have very different neutron-to-proton (N/Z) ratios than in stable nuclei. Light, neutron-rich isotopes exhibit the most asymmetric N/Z ratios and those lying beyond the limits of binding, which undergo spontaneous neutron emission and exist only as very short-lived resonances (about 10-21 s), provide the most stringent tests of modern nuclear-structure theories. Here we report on the first observation of 28O and 27O through their decay into 24O and four and three neutrons, respectively. The 28O nucleus is of particular interest as, with the Z = 8 and N = 20 magic numbers1,2, it is expected in the standard shell-model picture of nuclear structure to be one of a relatively small number of so-called 'doubly magic' nuclei. Both 27O and 28O were found to exist as narrow, low-lying resonances and their decay energies are compared here to the results of sophisticated theoretical modelling, including a large-scale shell-model calculation and a newly developed statistical approach. In both cases, the underlying nuclear interactions were derived from effective field theories of quantum chromodynamics. Finally, it is shown that the cross-section for the production of 28O from a 29F beam is consistent with it not exhibiting a closed N = 20 shell structure.
Collapse
Affiliation(s)
- Y Kondo
- Department of Physics, Tokyo Institute of Technology, Tokyo, Japan.
- RIKEN Nishina Center, Saitama, Japan.
| | - N L Achouri
- LPC Caen UMR6534, Université de Caen Normandie, ENSICAEN, CNRS/IN2P3, Caen, France
| | - H Al Falou
- Lebanese University, Beirut, Lebanon
- Lebanese-French University of Technology and Applied Sciences, Deddeh, Lebanon
| | - L Atar
- Institut für Kernphysik, Technische Universität Darmstadt, Darmstadt, Germany
| | - T Aumann
- Institut für Kernphysik, Technische Universität Darmstadt, Darmstadt, Germany
- GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany
- Helmholtz Research Academy Hesse for FAIR, Darmstadt, Germany
| | - H Baba
- RIKEN Nishina Center, Saitama, Japan
| | - K Boretzky
- GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany
| | - C Caesar
- Institut für Kernphysik, Technische Universität Darmstadt, Darmstadt, Germany
- GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany
| | - D Calvet
- Irfu, CEA, Université Paris-Saclay, Gif-sur-Yvette, France
| | - H Chae
- Institute for Basic Science, Daejeon, Republic of Korea
| | - N Chiga
- RIKEN Nishina Center, Saitama, Japan
| | - A Corsi
- Irfu, CEA, Université Paris-Saclay, Gif-sur-Yvette, France
| | - F Delaunay
- LPC Caen UMR6534, Université de Caen Normandie, ENSICAEN, CNRS/IN2P3, Caen, France
| | - A Delbart
- Irfu, CEA, Université Paris-Saclay, Gif-sur-Yvette, France
| | - Q Deshayes
- LPC Caen UMR6534, Université de Caen Normandie, ENSICAEN, CNRS/IN2P3, Caen, France
| | | | - C A Douma
- ESRIG, University of Groningen, Groningen, The Netherlands
| | - A Ekström
- Institutionen för Fysik, Chalmers Tekniska Högskola, Göteborg, Sweden
| | | | - C Forssén
- Institutionen för Fysik, Chalmers Tekniska Högskola, Göteborg, Sweden
| | - I Gašparić
- RIKEN Nishina Center, Saitama, Japan
- Institut für Kernphysik, Technische Universität Darmstadt, Darmstadt, Germany
- Ruđer Bošković Institute, Zagreb, Croatia
| | - J-M Gheller
- Irfu, CEA, Université Paris-Saclay, Gif-sur-Yvette, France
| | - J Gibelin
- LPC Caen UMR6534, Université de Caen Normandie, ENSICAEN, CNRS/IN2P3, Caen, France
| | - A Gillibert
- Irfu, CEA, Université Paris-Saclay, Gif-sur-Yvette, France
| | - G Hagen
- Physics Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
- Department of Physics and Astronomy, University of Tennessee, Knoxville, TN, USA
| | - M N Harakeh
- GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany
- ESRIG, University of Groningen, Groningen, The Netherlands
| | - A Hirayama
- Department of Physics, Tokyo Institute of Technology, Tokyo, Japan
| | - C R Hoffman
- Physics Division, Argonne National Laboratory, Argonne, IL, USA
| | - M Holl
- Institut für Kernphysik, Technische Universität Darmstadt, Darmstadt, Germany
- GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany
| | - A Horvat
- GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany
| | - Á Horváth
- Eötvös Loránd University, Budapest, Hungary
| | - J W Hwang
- Center for Exotic Nuclear Studies, Institute for Basic Science, Daejeon, Republic of Korea
- Department of Physics and Astronomy, Seoul National University, Seoul, Republic of Korea
| | - T Isobe
- RIKEN Nishina Center, Saitama, Japan
| | - W G Jiang
- Institutionen för Fysik, Chalmers Tekniska Högskola, Göteborg, Sweden
| | - J Kahlbow
- RIKEN Nishina Center, Saitama, Japan
- Institut für Kernphysik, Technische Universität Darmstadt, Darmstadt, Germany
| | | | - S Kawase
- Department of Advanced Energy Engineering Science, Kyushu University, Fukuoka, Japan
| | - S Kim
- Center for Exotic Nuclear Studies, Institute for Basic Science, Daejeon, Republic of Korea
- Department of Physics and Astronomy, Seoul National University, Seoul, Republic of Korea
| | | | - T Kobayashi
- Department of Physics, Tohoku University, Miyagi, Japan
| | - D Körper
- GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany
| | - S Koyama
- Department of Physics, The University of Tokyo, Tokyo, Japan
| | - I Kuti
- Atomki, Debrecen, Hungary
| | - V Lapoux
- Irfu, CEA, Université Paris-Saclay, Gif-sur-Yvette, France
| | - S Lindberg
- Institutionen för Fysik, Chalmers Tekniska Högskola, Göteborg, Sweden
| | - F M Marqués
- LPC Caen UMR6534, Université de Caen Normandie, ENSICAEN, CNRS/IN2P3, Caen, France
| | - S Masuoka
- Center for Nuclear Study, The University of Tokyo, Saitama, Japan
| | - J Mayer
- Institut für Kernphysik, Universität zu Köln, Köln, Germany
| | - K Miki
- Department of Physics, Tohoku University, Miyagi, Japan
| | - T Murakami
- Department of Physics, Kyoto University, Kyoto, Japan
| | - M Najafi
- ESRIG, University of Groningen, Groningen, The Netherlands
| | - T Nakamura
- Department of Physics, Tokyo Institute of Technology, Tokyo, Japan
- RIKEN Nishina Center, Saitama, Japan
| | - K Nakano
- Department of Advanced Energy Engineering Science, Kyushu University, Fukuoka, Japan
| | - N Nakatsuka
- Department of Physics, Kyoto University, Kyoto, Japan
| | - T Nilsson
- Institutionen för Fysik, Chalmers Tekniska Högskola, Göteborg, Sweden
| | - A Obertelli
- Irfu, CEA, Université Paris-Saclay, Gif-sur-Yvette, France
| | - K Ogata
- Department of Physics, Kyushu University, Fukuoka, Japan
- Research Center for Nuclear Physics, Osaka University, Osaka, Japan
- Department of Physics, Osaka City University, Osaka, Japan
| | - F de Oliveira Santos
- Grand Accélérateur National d'Ions Lourds (GANIL), CEA/DRF-CNRS/IN2P3, Caen, France
| | - N A Orr
- LPC Caen UMR6534, Université de Caen Normandie, ENSICAEN, CNRS/IN2P3, Caen, France
| | - H Otsu
- RIKEN Nishina Center, Saitama, Japan
| | - T Otsuka
- RIKEN Nishina Center, Saitama, Japan
- Department of Physics, The University of Tokyo, Tokyo, Japan
| | - T Ozaki
- Department of Physics, Tokyo Institute of Technology, Tokyo, Japan
| | - V Panin
- RIKEN Nishina Center, Saitama, Japan
| | - T Papenbrock
- Physics Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
- Department of Physics and Astronomy, University of Tennessee, Knoxville, TN, USA
| | - S Paschalis
- Institut für Kernphysik, Technische Universität Darmstadt, Darmstadt, Germany
| | - A Revel
- LPC Caen UMR6534, Université de Caen Normandie, ENSICAEN, CNRS/IN2P3, Caen, France
- Grand Accélérateur National d'Ions Lourds (GANIL), CEA/DRF-CNRS/IN2P3, Caen, France
| | - D Rossi
- Institut für Kernphysik, Technische Universität Darmstadt, Darmstadt, Germany
| | - A T Saito
- Department of Physics, Tokyo Institute of Technology, Tokyo, Japan
| | - T Y Saito
- Department of Physics, The University of Tokyo, Tokyo, Japan
| | - M Sasano
- RIKEN Nishina Center, Saitama, Japan
| | - H Sato
- RIKEN Nishina Center, Saitama, Japan
| | - Y Satou
- Department of Physics and Astronomy, Seoul National University, Seoul, Republic of Korea
| | - H Scheit
- Institut für Kernphysik, Technische Universität Darmstadt, Darmstadt, Germany
| | - F Schindler
- Institut für Kernphysik, Technische Universität Darmstadt, Darmstadt, Germany
| | - P Schrock
- Center for Nuclear Study, The University of Tokyo, Saitama, Japan
| | - M Shikata
- Department of Physics, Tokyo Institute of Technology, Tokyo, Japan
| | - N Shimizu
- Center for Computational Sciences, University of Tsukuba, Ibaraki, Japan
| | - Y Shimizu
- RIKEN Nishina Center, Saitama, Japan
| | - H Simon
- GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany
| | | | - O Sorlin
- Grand Accélérateur National d'Ions Lourds (GANIL), CEA/DRF-CNRS/IN2P3, Caen, France
| | - L Stuhl
- RIKEN Nishina Center, Saitama, Japan
- Center for Exotic Nuclear Studies, Institute for Basic Science, Daejeon, Republic of Korea
| | - Z H Sun
- Physics Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
- Department of Physics and Astronomy, University of Tennessee, Knoxville, TN, USA
| | - S Takeuchi
- Department of Physics, Tokyo Institute of Technology, Tokyo, Japan
| | - M Tanaka
- Department of Physics, Osaka University, Osaka, Japan
| | - M Thoennessen
- Facility for Rare Isotope Beams, Michigan State University, East Lansing, MI, USA
| | - H Törnqvist
- Institut für Kernphysik, Technische Universität Darmstadt, Darmstadt, Germany
- GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany
| | - Y Togano
- Department of Physics, Tokyo Institute of Technology, Tokyo, Japan
- Department of Physics, Rikkyo University, Tokyo, Japan
| | - T Tomai
- Department of Physics, Tokyo Institute of Technology, Tokyo, Japan
| | - J Tscheuschner
- Institut für Kernphysik, Technische Universität Darmstadt, Darmstadt, Germany
| | - J Tsubota
- Department of Physics, Tokyo Institute of Technology, Tokyo, Japan
| | - N Tsunoda
- Center for Nuclear Study, The University of Tokyo, Saitama, Japan
| | - T Uesaka
- RIKEN Nishina Center, Saitama, Japan
| | - Y Utsuno
- Advanced Science Research Center, Japan Atomic Energy Agency, Ibaraki, Japan
| | - I Vernon
- Department of Mathematical Sciences, Durham University, Durham, UK
| | - H Wang
- RIKEN Nishina Center, Saitama, Japan
| | - Z Yang
- RIKEN Nishina Center, Saitama, Japan
| | - M Yasuda
- Department of Physics, Tokyo Institute of Technology, Tokyo, Japan
| | - K Yoneda
- RIKEN Nishina Center, Saitama, Japan
| | - S Yoshida
- Liberal and General Education Center, Institute for Promotion of Higher Academic Education, Utsunomiya University, Tochigi, Japan
| |
Collapse
|
4
|
Ahn DS, Amano J, Baba H, Fukuda N, Geissel H, Inabe N, Ishikawa S, Iwasa N, Komatsubara T, Kubo T, Kusaka K, Morrissey DJ, Nakamura T, Ohtake M, Otsu H, Sakakibara T, Sato H, Sherrill BM, Shimizu Y, Sumikama T, Suzuki H, Takeda H, Tarasov OB, Ueno H, Yanagisawa Y, Yoshida K. Discovery of ^{39}Na. PHYSICAL REVIEW LETTERS 2022; 129:212502. [PMID: 36461972 DOI: 10.1103/physrevlett.129.212502] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2022] [Revised: 09/08/2022] [Accepted: 09/14/2022] [Indexed: 06/17/2023]
Abstract
The new isotope ^{39}Na, the most neutron-rich sodium nucleus observed so far, was discovered at the RIKEN Nishina Center Radioactive Isotope Beam Factory using the projectile fragmentation of an intense ^{48}Ca beam at 345 MeV/nucleon on a beryllium target. Projectile fragments were separated and identified in flight with the large-acceptance two-stage separator BigRIPS. Nine ^{39}Na events have been unambiguously observed in this work and clearly establish the particle stability of ^{39}Na. Furthermore, the lack of observation of ^{35,36}Ne isotopes in this experiment significantly improves the overall confidence that ^{34}Ne is the neutron dripline nucleus of neon. These results provide new key information to understand nuclear binding and nuclear structure under extremely neutron-rich conditions. The newly established stability of ^{39}Na has a significant impact on nuclear models and theories predicting the neutron dripline and also provides a key to understanding the nuclear shell property of ^{39}Na at the neutron number N=28, which is normally a magic number.
Collapse
Affiliation(s)
- D S Ahn
- RIKEN Nishina Center for Accelerator-Based Science, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - J Amano
- Department of Physics, Rikkyo University, 3-34-1 Nishi-Ikebukuro, Toshima, Tokyo 171-8501, Japan
| | - H Baba
- RIKEN Nishina Center for Accelerator-Based Science, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - N Fukuda
- RIKEN Nishina Center for Accelerator-Based Science, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - H Geissel
- GSI, Helmholtzzentrum für Schwerionenforschung GmbH, Planckstraße 1, 64291 Darmstadt, Germany
| | - N Inabe
- RIKEN Nishina Center for Accelerator-Based Science, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - S Ishikawa
- Department of Physics, Tohoku University, 6-3, Aramaki Aza-Aoba, Aoba-ku, Sendai, Miyagi 980-8578, Japan
| | - N Iwasa
- Department of Physics, Tohoku University, 6-3, Aramaki Aza-Aoba, Aoba-ku, Sendai, Miyagi 980-8578, Japan
| | - T Komatsubara
- RIKEN Nishina Center for Accelerator-Based Science, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - T Kubo
- RIKEN Nishina Center for Accelerator-Based Science, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - K Kusaka
- RIKEN Nishina Center for Accelerator-Based Science, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - D J Morrissey
- National Superconducting Cyclotron Laboratory, Michigan State University, 640 South Shaw Lane, East Lansing, Michigan 48824, USA
| | - T Nakamura
- Department of Physics, Tokyo Institute of Technology, 2-12-1 O-Okayama, Meguro, Tokyo 152-8551, Japan
| | - M Ohtake
- RIKEN Nishina Center for Accelerator-Based Science, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - H Otsu
- RIKEN Nishina Center for Accelerator-Based Science, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - T Sakakibara
- Department of Physics, Tohoku University, 6-3, Aramaki Aza-Aoba, Aoba-ku, Sendai, Miyagi 980-8578, Japan
| | - H Sato
- RIKEN Nishina Center for Accelerator-Based Science, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - B M Sherrill
- National Superconducting Cyclotron Laboratory, Michigan State University, 640 South Shaw Lane, East Lansing, Michigan 48824, USA
| | - Y Shimizu
- RIKEN Nishina Center for Accelerator-Based Science, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - T Sumikama
- RIKEN Nishina Center for Accelerator-Based Science, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - H Suzuki
- RIKEN Nishina Center for Accelerator-Based Science, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - H Takeda
- RIKEN Nishina Center for Accelerator-Based Science, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - O B Tarasov
- National Superconducting Cyclotron Laboratory, Michigan State University, 640 South Shaw Lane, East Lansing, Michigan 48824, USA
| | - H Ueno
- RIKEN Nishina Center for Accelerator-Based Science, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Y Yanagisawa
- RIKEN Nishina Center for Accelerator-Based Science, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - K Yoshida
- RIKEN Nishina Center for Accelerator-Based Science, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| |
Collapse
|