1
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Niwase T, Watanabe YX, Hirayama Y, Mukai M, Schury P, Andreyev AN, Hashimoto T, Iimura S, Ishiyama H, Ito Y, Jeong SC, Kaji D, Kimura S, Miyatake H, Morimoto K, Moon JY, Oyaizu M, Rosenbusch M, Taniguchi A, Wada M. Discovery of New Isotope ^{241}U and Systematic High-Precision Atomic Mass Measurements of Neutron-Rich Pa-Pu Nuclei Produced via Multinucleon Transfer Reactions. Phys Rev Lett 2023; 130:132502. [PMID: 37067317 DOI: 10.1103/physrevlett.130.132502] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Revised: 01/26/2023] [Accepted: 02/16/2023] [Indexed: 06/19/2023]
Abstract
The new isotope ^{241}U was synthesized and systematic atomic mass measurements of nineteen neutron-rich Pa-Pu isotopes were performed in the multinucleon transfer reactions of the ^{238}U+^{198}Pt system at the KISS facility. The present experimental results demonstrate the crucial role of the multinucleon transfer reactions for accessing unexplored neutron-rich actinide isotopes toward the N=152 shell gap in this region of nuclides.
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Affiliation(s)
- T Niwase
- Wako Nuclear Science Center, Institute of Particle and Nuclear Studies, High Energy Accelerator Research Organization (KEK), Wako, Saitama 351-0198, Japan
| | - Y X Watanabe
- Wako Nuclear Science Center, Institute of Particle and Nuclear Studies, High Energy Accelerator Research Organization (KEK), Wako, Saitama 351-0198, Japan
| | - Y Hirayama
- Wako Nuclear Science Center, Institute of Particle and Nuclear Studies, High Energy Accelerator Research Organization (KEK), Wako, Saitama 351-0198, Japan
| | - M Mukai
- RIKEN Nishina Center for Accelerator-Based Science, Wako, Saitama 351-0198, Japan
| | - P Schury
- Wako Nuclear Science Center, Institute of Particle and Nuclear Studies, High Energy Accelerator Research Organization (KEK), Wako, Saitama 351-0198, Japan
| | - A N Andreyev
- School of Physics, Engineering and Technology, University of York, York YO10 5DD, United Kingdom
| | - T Hashimoto
- Institute for Basic Science, 70, Yuseong-daero 1689-gil, Yusung-gu, Daejeon 43000, Korea
| | - S Iimura
- Department of Physics, Rikkyo University, Tokyo 171-8501, Japan
| | - H Ishiyama
- RIKEN Nishina Center for Accelerator-Based Science, Wako, Saitama 351-0198, Japan
| | - Y Ito
- Advanced Science Research Center, Japan Atomic Energy Agency, Ibaraki 319-1195, Japan
| | - S C Jeong
- Wako Nuclear Science Center, Institute of Particle and Nuclear Studies, High Energy Accelerator Research Organization (KEK), Wako, Saitama 351-0198, Japan
| | - D Kaji
- RIKEN Nishina Center for Accelerator-Based Science, Wako, Saitama 351-0198, Japan
| | - S Kimura
- RIKEN Nishina Center for Accelerator-Based Science, Wako, Saitama 351-0198, Japan
| | - H Miyatake
- Wako Nuclear Science Center, Institute of Particle and Nuclear Studies, High Energy Accelerator Research Organization (KEK), Wako, Saitama 351-0198, Japan
| | - K Morimoto
- RIKEN Nishina Center for Accelerator-Based Science, Wako, Saitama 351-0198, Japan
| | - J-Y Moon
- Institute for Basic Science, 70, Yuseong-daero 1689-gil, Yusung-gu, Daejeon 43000, Korea
| | - M Oyaizu
- Wako Nuclear Science Center, Institute of Particle and Nuclear Studies, High Energy Accelerator Research Organization (KEK), Wako, Saitama 351-0198, Japan
| | - M Rosenbusch
- Wako Nuclear Science Center, Institute of Particle and Nuclear Studies, High Energy Accelerator Research Organization (KEK), Wako, Saitama 351-0198, Japan
| | - A Taniguchi
- Institute for Integrated Radiation and Nuclear Science, Kyoto University, Kumatori, Osaka 590-0494, Japan
| | - M Wada
- Wako Nuclear Science Center, Institute of Particle and Nuclear Studies, High Energy Accelerator Research Organization (KEK), Wako, Saitama 351-0198, Japan
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2
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Iimura S, Rosenbusch M, Takamine A, Tsunoda Y, Wada M, Chen S, Hou DS, Xian W, Ishiyama H, Yan S, Schury P, Crawford H, Doornenbal P, Hirayama Y, Ito Y, Kimura S, Koiwai T, Kojima TM, Koura H, Lee J, Liu J, Michimasa S, Miyatake H, Moon JY, Naimi S, Nishimura S, Niwase T, Odahara A, Otsuka T, Paschalis S, Petri M, Shimizu N, Sonoda T, Suzuki D, Watanabe YX, Wimmer K, Wollnik H. Study of the N=32 and N=34 Shell Gap for Ti and V by the First High-Precision Multireflection Time-of-Flight Mass Measurements at BigRIPS-SLOWRI. Phys Rev Lett 2023; 130:012501. [PMID: 36669221 DOI: 10.1103/physrevlett.130.012501] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Accepted: 11/22/2022] [Indexed: 06/17/2023]
Abstract
The atomic masses of ^{55}Sc, ^{56,58}Ti, and ^{56-59}V have been determined using the high-precision multireflection time-of-flight technique. The radioisotopes have been produced at RIKEN's Radioactive Isotope Beam Factory (RIBF) and delivered to the novel designed gas cell and multireflection system, which has been recently commissioned downstream of the ZeroDegree spectrometer following the BigRIPS separator. For ^{56,58}Ti and ^{56-59}V, the mass uncertainties have been reduced down to the order of 10 keV, shedding new light on the N=34 shell effect in Ti and V isotopes by the first high-precision mass measurements of the critical species ^{58}Ti and ^{59}V. With the new precision achieved, we reveal the nonexistence of the N=34 empirical two-neutron shell gaps for Ti and V, and the enhanced energy gap above the occupied νp_{3/2} orbit is identified as a feature unique to Ca. We perform new Monte Carlo shell model calculations including the νd_{5/2} and νg_{9/2} orbits and compare the results with conventional shell model calculations, which exclude the νg_{9/2} and the νd_{5/2} orbits. The comparison indicates that the shell gap reduction in Ti is related to a partial occupation of the higher orbitals for the outer two valence neutrons at N=34.
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Affiliation(s)
- S Iimura
- RIKEN Nishina Center for Accelerator-Based Science, Wako, Saitama 351-0198, Japan
- Department of Physics, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043, Japan
- Wako Nuclear Science Center (WNSC), Institute of Particle and Nuclear Studies (IPNS), High Energy Accelerator Research Organization (KEK), Wako, Saitama 351-0198, Japan
- Department of Physics, College of Science, Rikkyo University, 3-34-1 Nishi-Ikebukuro, Tokyo 171-8501, Japan
| | - M Rosenbusch
- Wako Nuclear Science Center (WNSC), Institute of Particle and Nuclear Studies (IPNS), High Energy Accelerator Research Organization (KEK), Wako, Saitama 351-0198, Japan
| | - A Takamine
- RIKEN Nishina Center for Accelerator-Based Science, Wako, Saitama 351-0198, Japan
| | - Y Tsunoda
- Center for Computational Sciences, University of Tsukuba, Tsukuba 305-8577, Japan
| | - M Wada
- Wako Nuclear Science Center (WNSC), Institute of Particle and Nuclear Studies (IPNS), High Energy Accelerator Research Organization (KEK), Wako, Saitama 351-0198, Japan
| | - S Chen
- Department of Physics, The University of Hong Kong, Pokfulam, Hong Kong, China
| | - D S Hou
- Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China
- University of Chinese Academy of Sciences, Beijing 100049, China
- School of Nuclear Science and Technology, Lanzhou University, Lanzhou 730000, China
| | - W Xian
- Department of Physics, The University of Hong Kong, Pokfulam, Hong Kong, China
| | - H Ishiyama
- RIKEN Nishina Center for Accelerator-Based Science, Wako, Saitama 351-0198, Japan
| | - S Yan
- Institute of Mass Spectrometry and Atmospheric Environment, Jinan University, Guangzhou 510632, China
| | - P Schury
- Wako Nuclear Science Center (WNSC), Institute of Particle and Nuclear Studies (IPNS), High Energy Accelerator Research Organization (KEK), Wako, Saitama 351-0198, Japan
| | - H Crawford
- Nuclear Science Division, Lawrence Berkeley National Laboratory, Berkeley, California 94523, USA
| | - P Doornenbal
- RIKEN Nishina Center for Accelerator-Based Science, Wako, Saitama 351-0198, Japan
| | - Y Hirayama
- Wako Nuclear Science Center (WNSC), Institute of Particle and Nuclear Studies (IPNS), High Energy Accelerator Research Organization (KEK), Wako, Saitama 351-0198, Japan
| | - Y Ito
- Advanced Science Research Center, Japan Atomic Energy Agency, Ibaraki 319-1195, Japan
| | - S Kimura
- RIKEN Nishina Center for Accelerator-Based Science, Wako, Saitama 351-0198, Japan
| | - T Koiwai
- RIKEN Nishina Center for Accelerator-Based Science, Wako, Saitama 351-0198, Japan
- Department of Physics, The University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-0033, Japan
| | - T M Kojima
- RIKEN Nishina Center for Accelerator-Based Science, Wako, Saitama 351-0198, Japan
| | - H Koura
- Advanced Science Research Center, Japan Atomic Energy Agency, Ibaraki 319-1195, Japan
| | - J Lee
- Department of Physics, The University of Hong Kong, Pokfulam, Hong Kong, China
| | - J Liu
- Department of Physics, The University of Hong Kong, Pokfulam, Hong Kong, China
- Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China
| | - S Michimasa
- Center of Nuclear Study (CNS), The University of Tokyo, Bunkyo 113-0033, Japan
| | - H Miyatake
- Wako Nuclear Science Center (WNSC), Institute of Particle and Nuclear Studies (IPNS), High Energy Accelerator Research Organization (KEK), Wako, Saitama 351-0198, Japan
| | - J Y Moon
- Institute for Basic Science, 70, Yuseong-daero 1689-gil, Yusung-gu, Daejeon 305-811, Korea
| | - S Naimi
- RIKEN Nishina Center for Accelerator-Based Science, Wako, Saitama 351-0198, Japan
| | - S Nishimura
- RIKEN Nishina Center for Accelerator-Based Science, Wako, Saitama 351-0198, Japan
| | - T Niwase
- RIKEN Nishina Center for Accelerator-Based Science, Wako, Saitama 351-0198, Japan
- Wako Nuclear Science Center (WNSC), Institute of Particle and Nuclear Studies (IPNS), High Energy Accelerator Research Organization (KEK), Wako, Saitama 351-0198, Japan
- Kyushu University, Hakozaki, Higashi-ku, Fukuoka 812-8581, Japan
| | - A Odahara
- Department of Physics, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043, Japan
| | - T Otsuka
- RIKEN Nishina Center for Accelerator-Based Science, Wako, Saitama 351-0198, Japan
- Advanced Science Research Center, Japan Atomic Energy Agency, Ibaraki 319-1195, Japan
- Department of Physics, The University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-0033, Japan
| | - S Paschalis
- School of Physics, Engineering, and Technology, University of York, York YO10 5DD, United Kingdom
| | - M Petri
- School of Physics, Engineering, and Technology, University of York, York YO10 5DD, United Kingdom
| | - N Shimizu
- Center for Computational Sciences, University of Tsukuba, Tsukuba 305-8577, Japan
| | - T Sonoda
- RIKEN Nishina Center for Accelerator-Based Science, Wako, Saitama 351-0198, Japan
| | - D Suzuki
- RIKEN Nishina Center for Accelerator-Based Science, Wako, Saitama 351-0198, Japan
| | - Y X Watanabe
- Wako Nuclear Science Center (WNSC), Institute of Particle and Nuclear Studies (IPNS), High Energy Accelerator Research Organization (KEK), Wako, Saitama 351-0198, Japan
| | - K Wimmer
- RIKEN Nishina Center for Accelerator-Based Science, Wako, Saitama 351-0198, Japan
- Department of Physics, The University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-0033, Japan
- GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany
| | - H Wollnik
- New Mexico State University, Las Cruces, New Mexico 88001, USA
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3
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Walker PM, Hirayama Y, Lane GJ, Watanabe H, Dracoulis GD, Ahmed M, Brunet M, Hashimoto T, Ishizawa S, Kondev FG, Litvinov YA, Miyatake H, Moon JY, Mukai M, Niwase T, Park JH, Podolyák Z, Rosenbusch M, Schury P, Wada M, Watanabe XY, Liang WY, Xu FR. Properties of ^{187}Ta Revealed through Isomeric Decay. Phys Rev Lett 2020; 125:192505. [PMID: 33216598 DOI: 10.1103/physrevlett.125.192505] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Accepted: 10/13/2020] [Indexed: 06/11/2023]
Abstract
Mass-separated ^{187}Ta_{114} in a high-spin isomeric state has been produced for the first time by multinucleon transfer reactions, employing an argon gas-stopping cell and laser ionization. Internal γ rays revealed a T_{1/2}=7.3±0.9 s isomer at 1778±1 keV, which decays through a rotational band with perturbations associated with the approach to a prolate-oblate shape transition. Model calculations show less influence from triaxiality compared to heavier elements in the same mass region. The isomer-decay reduced E2 hindrance factor f_{ν}=27±1 supports the interpretation that axial symmetry is approximately conserved.
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Affiliation(s)
- P M Walker
- Department of Physics, University of Surrey, Guildford, GU2 7XH, United Kingdom
| | - Y Hirayama
- Wako Nuclear Science Center (WNSC), Institute of Particle and Nuclear Studies (IPNS), High Energy Accelerator Research Organization (KEK), Wako, Saitama 351-0198, Japan
| | - G J Lane
- Department of Nuclear Physics, RSPhys, Australian National University, Canberra, Australian Capital Territory 2601, Australia
| | - H Watanabe
- School of Physics, and International Research Center for Nuclei and Particles in Cosmos, Beihang University, Beijing 100191, China
- Nishina Center for Accelerator-Based Science, RIKEN, Wako, Saitama 351-0198, Japan
| | - G D Dracoulis
- Department of Nuclear Physics, RSPhys, Australian National University, Canberra, Australian Capital Territory 2601, Australia
| | - M Ahmed
- Wako Nuclear Science Center (WNSC), Institute of Particle and Nuclear Studies (IPNS), High Energy Accelerator Research Organization (KEK), Wako, Saitama 351-0198, Japan
- University of Tsukuba, Tsukuba, Ibaraki 305-0006, Japan
| | - M Brunet
- Department of Physics, University of Surrey, Guildford, GU2 7XH, United Kingdom
| | - T Hashimoto
- Rare Isotope Science Project, Institute for Basic Science (IBS), Daejeon 305-811, Republic of Korea
| | - S Ishizawa
- Wako Nuclear Science Center (WNSC), Institute of Particle and Nuclear Studies (IPNS), High Energy Accelerator Research Organization (KEK), Wako, Saitama 351-0198, Japan
- Nishina Center for Accelerator-Based Science, RIKEN, Wako, Saitama 351-0198, Japan
- Graduate School of Science and Engineering, Yamagata University, Yamagata 992-8510, Japan
| | - F G Kondev
- Physics Division, Argonne National Laboratory, Lemont, Illinois 60439, USA
| | - Yu A Litvinov
- GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany
| | - H Miyatake
- Wako Nuclear Science Center (WNSC), Institute of Particle and Nuclear Studies (IPNS), High Energy Accelerator Research Organization (KEK), Wako, Saitama 351-0198, Japan
| | - J Y Moon
- Rare Isotope Science Project, Institute for Basic Science (IBS), Daejeon 305-811, Republic of Korea
| | - M Mukai
- Wako Nuclear Science Center (WNSC), Institute of Particle and Nuclear Studies (IPNS), High Energy Accelerator Research Organization (KEK), Wako, Saitama 351-0198, Japan
- Nishina Center for Accelerator-Based Science, RIKEN, Wako, Saitama 351-0198, Japan
- University of Tsukuba, Tsukuba, Ibaraki 305-0006, Japan
| | - T Niwase
- Wako Nuclear Science Center (WNSC), Institute of Particle and Nuclear Studies (IPNS), High Energy Accelerator Research Organization (KEK), Wako, Saitama 351-0198, Japan
- Nishina Center for Accelerator-Based Science, RIKEN, Wako, Saitama 351-0198, Japan
- Department of Physics, Kyushu University, Nishi-ku, Fukuoka 819-0395, Japan
| | - J H Park
- Rare Isotope Science Project, Institute for Basic Science (IBS), Daejeon 305-811, Republic of Korea
| | - Zs Podolyák
- Department of Physics, University of Surrey, Guildford, GU2 7XH, United Kingdom
| | - M Rosenbusch
- Wako Nuclear Science Center (WNSC), Institute of Particle and Nuclear Studies (IPNS), High Energy Accelerator Research Organization (KEK), Wako, Saitama 351-0198, Japan
| | - P Schury
- Wako Nuclear Science Center (WNSC), Institute of Particle and Nuclear Studies (IPNS), High Energy Accelerator Research Organization (KEK), Wako, Saitama 351-0198, Japan
| | - M Wada
- Wako Nuclear Science Center (WNSC), Institute of Particle and Nuclear Studies (IPNS), High Energy Accelerator Research Organization (KEK), Wako, Saitama 351-0198, Japan
- University of Tsukuba, Tsukuba, Ibaraki 305-0006, Japan
| | - X Y Watanabe
- Wako Nuclear Science Center (WNSC), Institute of Particle and Nuclear Studies (IPNS), High Energy Accelerator Research Organization (KEK), Wako, Saitama 351-0198, Japan
| | - W Y Liang
- School of Physics and State Key Laboratory of Nuclear Physics and Technology, Peking University, Beijing 100871, China
| | - F R Xu
- School of Physics and State Key Laboratory of Nuclear Physics and Technology, Peking University, Beijing 100871, China
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4
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Schury P, Wada M, Wollnik H, Moon JY, Hashimoto T, Rosenbusch M. High-stability, high-voltage power supplies for use with multi-reflection time-of-flight mass spectrographs. Rev Sci Instrum 2020; 91:014702. [PMID: 32012634 DOI: 10.1063/1.5104292] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2019] [Accepted: 12/10/2019] [Indexed: 06/10/2023]
Abstract
Achieving the highest possible mass resolving power in a multireflection time-of-flight mass spectrometer requires very high-stability power supplies. To this end, we have developed a programmable high-voltage power supply that can achieve long-term stability in the order of parts-per-million. Herein, we present the design of a stable high-voltage system and bench-top stability measurements up to 1 kV; a stabilization technique can, in principle, be applied up to 15 kV or more. We demonstrate that in the ≤1 Hz band, the output stability is at the level of 1 part per million (ppm) for 1 h, with only slightly more output variation across 3 days. We further demonstrate that the output is largely free of noise in the 1 Hz-200 Hz band. We also demonstrate settling to the ppm level within 1 min following a 100 V step transition. Finally, we demonstrate that when these power supplies are used to bias the electrodes of a multireflection time-of-flight mass spectrograph, the measured time-of-flight is stable at the ppm-level for at least 1 h.
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Affiliation(s)
- P Schury
- Institute of Particle and Nuclear Studies (IPNS), High Energy Accelerator Research Organization (KEK), Ibaraki 305-0801, Japan
| | - M Wada
- Institute of Particle and Nuclear Studies (IPNS), High Energy Accelerator Research Organization (KEK), Ibaraki 305-0801, Japan
| | - H Wollnik
- New Mexico State University, Las Cruces, New Mexico 88001, USA
| | - J-Y Moon
- Institute for Basic Science, Daejeon 34126, South Korea
| | - T Hashimoto
- Institute for Basic Science, Daejeon 34126, South Korea
| | - M Rosenbusch
- RIKEN Nishina Center for Accelerator-Based Science, Saitama 351-0198, Japan
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5
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Hirayama Y, Mukai M, Watanabe YX, Oyaizu M, Jeong SC, Kakiguchi Y, Schury P, Wada M, Miyatake H. Efficient two-color two-step laser ionization schemes of λ 1∼ 250 nm and λ 2 = 307.9 nm for heavy refractory elements-Measurements of ionization cross-sections and hyperfine spectra of tantalum and tungsten. Rev Sci Instrum 2019; 90:115104. [PMID: 31779376 DOI: 10.1063/1.5124444] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2019] [Accepted: 10/17/2019] [Indexed: 06/10/2023]
Abstract
We demonstrated efficient two-color two-step laser ionization schemes in the combined use of λ1 ∼ 250 nm and λ2 = 307.9 nm, which are applicable to heavy refractory elements with an atomic number in the wide range of Z = 69-78. We investigated newly observed ionization schemes of tantalum and tungsten atoms in an argon-gas-cell-based laser ion source for the efficient ionization of atoms of unstable nuclei through the two-color two-step laser resonance ionization technique. We experimentally determined the ionization cross sections from the measured saturation curves by solving the rate equations for the ground, intermediate, and ionization continuum populations. Hyperfine structures of these elements were also studied to deduce the isotope-shift, pressure-shift, and pressure-broadening in the resonance spectra of the excitation transitions in the argon gas cell. The electronic factor F255 of the excitation transition λ1 = 255.2115 nm between the ground and intermediate states was deduced from the measured isotope shifts of stable 182,183,184,186W isotopes. The ionization schemes investigated here are applicable to extract any isotopes of these elements by considering the measured pressure shift and nuclear isotope shift in optimizing the wavelength λ1.
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Affiliation(s)
- Y Hirayama
- Wako Nuclear Science Center (WNSC), Institute of Particle and Nuclear Studies (IPNS), High Energy Accelerator Research Organization (KEK), Saitama 351-0198, Japan
| | - M Mukai
- Graduate School of Pure and Applied Sciences, University of Tsukuba, Ibaraki 305-0006, Japan
| | - Y X Watanabe
- Wako Nuclear Science Center (WNSC), Institute of Particle and Nuclear Studies (IPNS), High Energy Accelerator Research Organization (KEK), Saitama 351-0198, Japan
| | - M Oyaizu
- Wako Nuclear Science Center (WNSC), Institute of Particle and Nuclear Studies (IPNS), High Energy Accelerator Research Organization (KEK), Saitama 351-0198, Japan
| | - S C Jeong
- Rare Isotope Science Project, Institute for Basic Science (IBS), Daejeon 305-811, South Korea
| | - Y Kakiguchi
- Wako Nuclear Science Center (WNSC), Institute of Particle and Nuclear Studies (IPNS), High Energy Accelerator Research Organization (KEK), Saitama 351-0198, Japan
| | - P Schury
- Wako Nuclear Science Center (WNSC), Institute of Particle and Nuclear Studies (IPNS), High Energy Accelerator Research Organization (KEK), Saitama 351-0198, Japan
| | - M Wada
- Wako Nuclear Science Center (WNSC), Institute of Particle and Nuclear Studies (IPNS), High Energy Accelerator Research Organization (KEK), Saitama 351-0198, Japan
| | - H Miyatake
- Wako Nuclear Science Center (WNSC), Institute of Particle and Nuclear Studies (IPNS), High Energy Accelerator Research Organization (KEK), Saitama 351-0198, Japan
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6
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Ito Y, Schury P, Wada M, Arai F, Haba H, Hirayama Y, Ishizawa S, Kaji D, Kimura S, Koura H, MacCormick M, Miyatake H, Moon JY, Morimoto K, Morita K, Mukai M, Murray I, Niwase T, Okada K, Ozawa A, Rosenbusch M, Takamine A, Tanaka T, Watanabe YX, Wollnik H, Yamaki S. First Direct Mass Measurements of Nuclides around Z=100 with a Multireflection Time-of-Flight Mass Spectrograph. Phys Rev Lett 2018; 120:152501. [PMID: 29756864 DOI: 10.1103/physrevlett.120.152501] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2017] [Revised: 02/05/2018] [Indexed: 06/08/2023]
Abstract
The masses of ^{246}Es, ^{251}Fm, and the transfermium nuclei ^{249-252}Md and ^{254}No, produced by hot- and cold-fusion reactions, in the vicinity of the deformed N=152 neutron shell closure, have been directly measured using a multireflection time-of-flight mass spectrograph. The masses of ^{246}Es and ^{249,250,252}Md were measured for the first time. Using the masses of ^{249,250}Md as anchor points for α decay chains, the masses of heavier nuclei, up to ^{261}Bh and ^{266}Mt, were determined. These new masses were compared with theoretical global mass models and demonstrated to be in good agreement with macroscopic-microscopic models in this region. The empirical shell gap parameter δ_{2n} derived from three isotopic masses was updated with the new masses and corroborates the existence of the deformed N=152 neutron shell closure for Md and Lr.
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Affiliation(s)
- Y Ito
- RIKEN Nishina Center for Accelerator-Based Science, Wako 351-0198, Japan
| | - P Schury
- Wako Nuclear Science Center (WNSC), Institute of Particle and Nuclear Studies (IPNS), High Energy Accelerator Research Organization (KEK), Wako 351-0198, Japan
| | - M Wada
- RIKEN Nishina Center for Accelerator-Based Science, Wako 351-0198, Japan
- Wako Nuclear Science Center (WNSC), Institute of Particle and Nuclear Studies (IPNS), High Energy Accelerator Research Organization (KEK), Wako 351-0198, Japan
| | - F Arai
- RIKEN Nishina Center for Accelerator-Based Science, Wako 351-0198, Japan
- University of Tsukuba, Tsukuba, Ibaraki 305-8577, Japan
| | - H Haba
- RIKEN Nishina Center for Accelerator-Based Science, Wako 351-0198, Japan
| | - Y Hirayama
- Wako Nuclear Science Center (WNSC), Institute of Particle and Nuclear Studies (IPNS), High Energy Accelerator Research Organization (KEK), Wako 351-0198, Japan
| | - S Ishizawa
- RIKEN Nishina Center for Accelerator-Based Science, Wako 351-0198, Japan
- Graduate School of Science and Engineering, Yamagata University, Yamagata 990-8560, Japan
| | - D Kaji
- RIKEN Nishina Center for Accelerator-Based Science, Wako 351-0198, Japan
| | - S Kimura
- RIKEN Nishina Center for Accelerator-Based Science, Wako 351-0198, Japan
- Wako Nuclear Science Center (WNSC), Institute of Particle and Nuclear Studies (IPNS), High Energy Accelerator Research Organization (KEK), Wako 351-0198, Japan
- University of Tsukuba, Tsukuba, Ibaraki 305-8577, Japan
| | - H Koura
- Japan Atomic Energy Agency, Tokai, Ibaraki 319-1185, Japan
| | - M MacCormick
- Institut de Physique Nucléaire, IN2P3-CNRS, Université Paris-Sud, Université Paris-Saclay, 91406 Orsay Cedex, France
| | - H Miyatake
- Wako Nuclear Science Center (WNSC), Institute of Particle and Nuclear Studies (IPNS), High Energy Accelerator Research Organization (KEK), Wako 351-0198, Japan
| | - J Y Moon
- Wako Nuclear Science Center (WNSC), Institute of Particle and Nuclear Studies (IPNS), High Energy Accelerator Research Organization (KEK), Wako 351-0198, Japan
- Rare Isotope Science Project, Institute for Basic Science (IBS), Daejeon 305-811, Korea
| | - K Morimoto
- RIKEN Nishina Center for Accelerator-Based Science, Wako 351-0198, Japan
| | - K Morita
- RIKEN Nishina Center for Accelerator-Based Science, Wako 351-0198, Japan
- Department of Physics, Kyushu University, Nishi-ku, Fukuoka 819-0395, Japan
| | - M Mukai
- Wako Nuclear Science Center (WNSC), Institute of Particle and Nuclear Studies (IPNS), High Energy Accelerator Research Organization (KEK), Wako 351-0198, Japan
- University of Tsukuba, Tsukuba, Ibaraki 305-8577, Japan
| | - I Murray
- RIKEN Nishina Center for Accelerator-Based Science, Wako 351-0198, Japan
| | - T Niwase
- Department of Physics, Kyushu University, Nishi-ku, Fukuoka 819-0395, Japan
| | - K Okada
- RIKEN Nishina Center for Accelerator-Based Science, Wako 351-0198, Japan
- Sophia University, Chiyoda-ku, Tokyo 102-8554, Japan
| | - A Ozawa
- University of Tsukuba, Tsukuba, Ibaraki 305-8577, Japan
| | - M Rosenbusch
- RIKEN Nishina Center for Accelerator-Based Science, Wako 351-0198, Japan
| | - A Takamine
- RIKEN Nishina Center for Accelerator-Based Science, Wako 351-0198, Japan
| | - T Tanaka
- RIKEN Nishina Center for Accelerator-Based Science, Wako 351-0198, Japan
- Department of Physics, Kyushu University, Nishi-ku, Fukuoka 819-0395, Japan
| | - Y X Watanabe
- Wako Nuclear Science Center (WNSC), Institute of Particle and Nuclear Studies (IPNS), High Energy Accelerator Research Organization (KEK), Wako 351-0198, Japan
| | - H Wollnik
- RIKEN Nishina Center for Accelerator-Based Science, Wako 351-0198, Japan
- Department of Chemistry and Biochemistry, New Mexico State University, Las Cruces, New Mexico 88003, USA
| | - S Yamaki
- RIKEN Nishina Center for Accelerator-Based Science, Wako 351-0198, Japan
- Department of Physics, Saitama University, Sakura-ku, Saitama 338-8570, Japan
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7
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Suzuki H, Sinclair L, Söderström PA, Lorusso G, Davies P, Ferreira LS, Maglione E, Wadsworth R, Wu J, Xu ZY, Nishimura S, Doornenbal P, Ahn DS, Browne F, Fukuda N, Inabe N, Kubo T, Lubos D, Patel Z, Rice S, Shimizu Y, Takeda H, Baba H, Estrade A, Fang Y, Henderson J, Isobe T, Jenkins D, Kubono S, Li Z, Nishizuka I, Sakurai H, Schury P, Sumikama T, Watanabe H, Werner V. Discovery of ^{72}Rb: A Nuclear Sandbank Beyond the Proton Drip Line. Phys Rev Lett 2017; 119:192503. [PMID: 29219499 DOI: 10.1103/physrevlett.119.192503] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2017] [Indexed: 06/07/2023]
Abstract
In this Letter, the observation of two previously unknown isotopes is presented for the first time: ^{72}Rb with 14 observed events and ^{77}Zr with one observed event. From the nonobservation of the less proton-rich nucleus ^{73}Rb, we derive an upper limit for the ground-state half-life of 81 ns, consistent with the previous upper limit of 30 ns. For ^{72}Rb, we have measured a half-life of 103(22) ns. This observation of a relatively long-lived odd-odd nucleus, ^{72}Rb, with a less exotic odd-even neighbor, ^{73}Rb, being unbound shows the diffuseness of the proton drip line and the possibility of sandbanks to exist beyond it. The ^{72}Rb half-life is consistent with a 5^{+}→5/2^{-} proton decay with an energy of 800-900 keV, in agreement with the atomic mass evaluation proton-separation energy as well as results from the finite-range droplet model and shell model calculations using the GXPF1A interaction. However, we cannot explicitly exclude the possibility of a proton transition between 9^{+}(^{72}Rb)→9/2^{+}(^{71}Kr) isomeric states with a broken mirror symmetry. These results imply that ^{72}Kr is a strong waiting point in x-ray burst rp-process scenarios.
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Affiliation(s)
- H Suzuki
- RIKEN Nishina Center, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
| | - L Sinclair
- RIKEN Nishina Center, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
- Department of Physics, University of York, Heslington, York YO10 5DD, United Kingdom
| | - P-A Söderström
- RIKEN Nishina Center, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
- Institut für Kernphysik, TU Darmstadt, D-64289 Darmstadt, Germany
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291 Darmstadt, Germany
| | - G Lorusso
- RIKEN Nishina Center, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
- National Physical Laboratory, Teddington, Middlesex TW11 0LW, United Kingdom
- Department of Physics, University of Surrey, Guildford GU2 7XH, United Kingdom
| | - P Davies
- Department of Physics, University of York, Heslington, York YO10 5DD, United Kingdom
| | - L S Ferreira
- Centro de Física e Engenharia de Materiais Avançados CeFEMA, Instituto Superior Técnico, Universidade de Lisboa, Avenida Rovisco Pais, P1049-001 Lisbon, Portugal
| | - E Maglione
- Dipartimento di Fisica e Astronomia "G. Galilei," and Istituto Nazionale di Fisica Nucleare, Via Marzolo 8, I-35131 Padova, Italy
| | - R Wadsworth
- Department of Physics, University of York, Heslington, York YO10 5DD, United Kingdom
| | - J Wu
- RIKEN Nishina Center, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
- Department of Physics, Peking University, Beijing 100871, China
| | - Z Y Xu
- Department of Physics, University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - S Nishimura
- RIKEN Nishina Center, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
| | - P Doornenbal
- RIKEN Nishina Center, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
| | - D S Ahn
- RIKEN Nishina Center, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
| | - F Browne
- RIKEN Nishina Center, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
- School of Computing, Engineering and Mathematics, University of Brighton, Brighton BN2 4GJ, United Kingdom
| | - N Fukuda
- RIKEN Nishina Center, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
| | - N Inabe
- RIKEN Nishina Center, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
| | - T Kubo
- RIKEN Nishina Center, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
| | - D Lubos
- RIKEN Nishina Center, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
- Physik Department E12, Technische Universität München, D-85748 Garching, Germany
| | - Z Patel
- RIKEN Nishina Center, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
- Department of Physics, University of Surrey, Guildford GU2 7XH, United Kingdom
| | - S Rice
- RIKEN Nishina Center, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
- Department of Physics, University of Surrey, Guildford GU2 7XH, United Kingdom
| | - Y Shimizu
- RIKEN Nishina Center, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
| | - H Takeda
- RIKEN Nishina Center, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
| | - H Baba
- RIKEN Nishina Center, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
| | - A Estrade
- School of Physics and Astronomy, University of Edinburgh, Edinburgh EH9 3JZ, United Kingdom
| | - Y Fang
- Department of Physics, Osaka University, Machikaneyama-machi 1-1, Osaka 560-0043 Toyonaka, Japan
| | - J Henderson
- Department of Physics, University of York, Heslington, York YO10 5DD, United Kingdom
| | - T Isobe
- RIKEN Nishina Center, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
| | - D Jenkins
- Department of Physics, University of York, Heslington, York YO10 5DD, United Kingdom
| | - S Kubono
- RIKEN Nishina Center, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
| | - Z Li
- Department of Physics, Peking University, Beijing 100871, China
| | - I Nishizuka
- Department of Physics, Tohoku University, Aoba, Sendai, Miyagi 980-8578, Japan
| | - H Sakurai
- RIKEN Nishina Center, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
- Department of Physics, University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - P Schury
- RIKEN Nishina Center, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
- Institute of Physics, University of Tsukuba, Ibaraki 305-8571, Japan
| | - T Sumikama
- Department of Physics, Tohoku University, Aoba, Sendai, Miyagi 980-8578, Japan
| | - H Watanabe
- International Research Center for Nuclei and Particles in the Cosmos, Beihang University, Beijing 100191, China
- School of Physics and Nuclear Energy Engineering, Beihang University, Beijing 100191, China
| | - V Werner
- Institut für Kernphysik, TU Darmstadt, D-64289 Darmstadt, Germany
- Wright Nuclear Structure Laboratory, Yale University, New Haven, Connecticut 06520-8120, USA
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8
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Lorusso G, Nishimura S, Xu ZY, Jungclaus A, Shimizu Y, Simpson GS, Söderström PA, Watanabe H, Browne F, Doornenbal P, Gey G, Jung HS, Meyer B, Sumikama T, Taprogge J, Vajta Z, Wu J, Baba H, Benzoni G, Chae KY, Crespi FCL, Fukuda N, Gernhäuser R, Inabe N, Isobe T, Kajino T, Kameda D, Kim GD, Kim YK, Kojouharov I, Kondev FG, Kubo T, Kurz N, Kwon YK, Lane GJ, Li Z, Montaner-Pizá A, Moschner K, Naqvi F, Niikura M, Nishibata H, Odahara A, Orlandi R, Patel Z, Podolyák Z, Sakurai H, Schaffner H, Schury P, Shibagaki S, Steiger K, Suzuki H, Takeda H, Wendt A, Yagi A, Yoshinaga K. β-Decay Half-Lives of 110 Neutron-Rich Nuclei across the N=82 Shell Gap: Implications for the Mechanism and Universality of the Astrophysical r Process. Phys Rev Lett 2015; 114:192501. [PMID: 26024165 DOI: 10.1103/physrevlett.114.192501] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2014] [Indexed: 06/04/2023]
Abstract
The β-decay half-lives of 110 neutron-rich isotopes of the elements from _{37}Rb to _{50}Sn were measured at the Radioactive Isotope Beam Factory. The 40 new half-lives follow robust systematics and highlight the persistence of shell effects. The new data have direct implications for r-process calculations and reinforce the notion that the second (A≈130) and the rare-earth-element (A≈160) abundance peaks may result from the freeze-out of an (n,γ)⇄(γ,n) equilibrium. In such an equilibrium, the new half-lives are important factors determining the abundance of rare-earth elements, and allow for a more reliable discussion of the r process universality. It is anticipated that universality may not extend to the elements Sn, Sb, I, and Cs, making the detection of these elements in metal-poor stars of the utmost importance to determine the exact conditions of individual r-process events.
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Affiliation(s)
- G Lorusso
- RIKEN Nishina Center, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
- National Physical Laboratory, Teddington, Middlesex TW11 0LW, United Kingdom
- Department of Physics, University of Surrey, Guildford GU2 7XH, United Kingdom
| | - S Nishimura
- RIKEN Nishina Center, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
- Division of Theoretical Astronomy, NAOJ, 181-8588 Mitaka, Japan
| | - Z Y Xu
- RIKEN Nishina Center, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
- Department of Physics, University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
- Department of Physics, the University of Hong Kong, Pokfulam Road, Hong Kong
| | - A Jungclaus
- Instituto de Estructura de la Materia, CSIC, E-28006 Madrid, Spain
| | - Y Shimizu
- RIKEN Nishina Center, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
| | - G S Simpson
- LPSC, Université Joseph Fourier Grenoble 1, CNRS/IN2P3, Institut National Polytechnique de Grenoble, F-38026 Grenoble Cedex, France
| | - P-A Söderström
- RIKEN Nishina Center, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
| | - H Watanabe
- RIKEN Nishina Center, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
- IRCNPC, School of Physics and Nuclear Energy Engineering, Beihang University, Beijing 100191, China
| | - F Browne
- RIKEN Nishina Center, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
- School of Computing, Engineering and Mathematics, University of Brighton, Brighton BN2 4JG, United Kingdom
| | - P Doornenbal
- RIKEN Nishina Center, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
| | - G Gey
- RIKEN Nishina Center, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
- LPSC, Université Joseph Fourier Grenoble 1, CNRS/IN2P3, Institut National Polytechnique de Grenoble, F-38026 Grenoble Cedex, France
| | - H S Jung
- Department of Physics, Chung-Ang University, Seoul 156-756, Republic of Korea
| | - B Meyer
- Department of Physics and Astronomy, Clemson University, Clemson, South Carolina 29634, USA
| | - T Sumikama
- Department of Physics, Tohoku University, Aoba, Sendai, Miyagi 980-8578, Japan
| | - J Taprogge
- RIKEN Nishina Center, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
- Instituto de Estructura de la Materia, CSIC, E-28006 Madrid, Spain
- Departamento de Física Teórica, Universidad Autónoma de Madrid, E-28049 Madrid, Spain
| | - Zs Vajta
- RIKEN Nishina Center, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
- Institute for Nuclear Research, Hungarian Academy of Sciences, P. O. Box 51, Debrecen H-4001, Hungary
| | - J Wu
- RIKEN Nishina Center, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
- Department of Physics, Peking University, Beijing 100871, China
| | - H Baba
- RIKEN Nishina Center, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
| | - G Benzoni
- INFN Sezione di Milano, I-20133 Milano, Italy
| | - K Y Chae
- Department of Physics, Sungkyunkwan University, Suwon 440-746, Republic of Korea
| | - F C L Crespi
- INFN Sezione di Milano, I-20133 Milano, Italy
- Dipartimento di Fisica, Università di Milano, I-20133 Milano, Italy
| | - N Fukuda
- RIKEN Nishina Center, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
| | - R Gernhäuser
- Physik Department E12, Technische Universität München, D-85748 Garching, Germany
| | - N Inabe
- RIKEN Nishina Center, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
| | - T Isobe
- RIKEN Nishina Center, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
| | - T Kajino
- Division of Theoretical Astronomy, NAOJ, 181-8588 Mitaka, Japan
- Department of Astronomy, University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - D Kameda
- RIKEN Nishina Center, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
| | - G D Kim
- Institute for Basic Science, Rare Isotope Science Project, Yuseong-daero 1689-gil, Yuseong-gu, 305-811 Daejeon, Republic of Korea
| | - Y-K Kim
- Institute for Basic Science, Rare Isotope Science Project, Yuseong-daero 1689-gil, Yuseong-gu, 305-811 Daejeon, Republic of Korea
- Department of Nuclear Engineering, Hanyang University, Seoul 133-791, Republic of Korea
| | - I Kojouharov
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291 Darmstadt, Germany
| | - F G Kondev
- Nuclear Engineering Division, Argonne National Laboratory, Argonne, Illinois 60439, USA
| | - T Kubo
- RIKEN Nishina Center, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
| | - N Kurz
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291 Darmstadt, Germany
| | - Y K Kwon
- Institute for Basic Science, Rare Isotope Science Project, Yuseong-daero 1689-gil, Yuseong-gu, 305-811 Daejeon, Republic of Korea
| | - G J Lane
- Department of Nuclear Physics, R.S.P.E., Australian National University, Canberra, Australian Capital Territory 0200, Australia
| | - Z Li
- Department of Physics, Peking University, Beijing 100871, China
| | - A Montaner-Pizá
- Instituto de Física Corpuscular, CSIC-University of Valencia, E-46980 Paterna, Spain
| | - K Moschner
- Institut für Kernphysik, Universität zu Köln, Zülpicher Strasse 77, D-50937 Köln, Germany
| | - F Naqvi
- Wright Nuclear Structure Laboratory, Yale University, New Haven, Connecticut 06520-8120, USA
| | - M Niikura
- Department of Physics, University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - H Nishibata
- Department of Physics, Osaka University, Machikaneyama-machi 1-1, Osaka 560-0043 Toyonaka, Japan
| | - A Odahara
- Department of Physics, Osaka University, Machikaneyama-machi 1-1, Osaka 560-0043 Toyonaka, Japan
| | - R Orlandi
- Instituut voor Kern en Stralingsfysica, KU Leuven, University of Leuven, B-3001 Leuven, Belgium
| | - Z Patel
- Department of Physics, University of Surrey, Guildford GU2 7XH, United Kingdom
| | - Zs Podolyák
- Department of Physics, University of Surrey, Guildford GU2 7XH, United Kingdom
| | - H Sakurai
- RIKEN Nishina Center, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
- Department of Physics, University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - H Schaffner
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291 Darmstadt, Germany
| | - P Schury
- RIKEN Nishina Center, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
| | - S Shibagaki
- Division of Theoretical Astronomy, NAOJ, 181-8588 Mitaka, Japan
- Department of Astronomy, University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - K Steiger
- Physik Department E12, Technische Universität München, D-85748 Garching, Germany
| | - H Suzuki
- RIKEN Nishina Center, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
| | - H Takeda
- RIKEN Nishina Center, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
| | - A Wendt
- Institut für Kernphysik, Universität zu Köln, Zülpicher Strasse 77, D-50937 Köln, Germany
| | - A Yagi
- Department of Physics, Osaka University, Machikaneyama-machi 1-1, Osaka 560-0043 Toyonaka, Japan
| | - K Yoshinaga
- Department of Physics, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba 278-8510, Japan
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9
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Takamine A, Wada M, Okada K, Sonoda T, Schury P, Nakamura T, Kanai Y, Kubo T, Katayama I, Ohtani S, Wollnik H, Schuessler HA. Hyperfine structure constant of the neutron halo nucleus (11)Be(+). Phys Rev Lett 2014; 112:162502. [PMID: 24815642 DOI: 10.1103/physrevlett.112.162502] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2012] [Indexed: 06/03/2023]
Abstract
The hyperfine splittings of ground state Be+11 have been measured precisely by laser-microwave double resonance spectroscopy for trapped and laser cooled beryllium ions. The ions were produced at relativistic energies and subsequently slowed down and trapped at mK temperatures. The magnetic hyperfine structure constant of Be+11 was determined to be A11=-2677.302 988(72) MHz from the measurements of the mF-mF'=0-0 field independent transition. This measurement provides essential data for the study of the distribution of the halo neutron in the single neutron halo nucleus Be11 through the Bohr-Weisskopf effect.
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Affiliation(s)
- A Takamine
- Nishina Center for Accelerator Based Science, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - M Wada
- Nishina Center for Accelerator Based Science, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - K Okada
- Department of Physics, Sophia University, 7-1 Kioicho, Chiyoda, Tokyo 102-8554, Japan
| | - T Sonoda
- Nishina Center for Accelerator Based Science, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - P Schury
- Nishina Center for Accelerator Based Science, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - T Nakamura
- Atomic Physics Laboratory, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Y Kanai
- Atomic Physics Laboratory, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - T Kubo
- Nishina Center for Accelerator Based Science, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - I Katayama
- Institute of Particle and Nuclear Studies, High Energy Accelerator Research Organization (KEK), Tsukuba, Ibaraki 305-0801, Japan
| | - S Ohtani
- Institute for Laser Science (ILS), The University of Electro-Communications, 1-5-1 Chofugaoka, Chofu, Tokyo 182-8585, Japan
| | - H Wollnik
- Department of Chemistry and Biochemistry, New Mexico State University, Las Cruces, New Mexico 88003, USA
| | - H A Schuessler
- Department of Physics, Texas A&M University, College Station, Texas 77843, USA
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10
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Sonoda T, Wada M, Tomita H, Sakamoto C, Takatsuka T, Noto T, Iimura H, Matsuo Y, Kubo T, Shinozuka T, Wakui T, Mita H, Naimi S, Furukawa T, Itou Y, Schury P, Miyatake H, Jeong S, Ishiyama H, Watanabe Y, Hirayama Y. Development of a gas cell-based laser ion source for RIKEN PALIS. ACTA ACUST UNITED AC 2013. [DOI: 10.1007/s10751-013-0817-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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11
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Savory J, Schury P, Bachelet C, Block M, Bollen G, Facina M, Folden CM, Guénaut C, Kwan E, Kwiatkowski AA, Morrissey DJ, Pang GK, Prinke A, Ringle R, Schatz H, Schwarz S, Sumithrarachchi CS. rp process and masses of N approximately Z approximately 34 nuclides. Phys Rev Lett 2009; 102:132501. [PMID: 19392349 DOI: 10.1103/physrevlett.102.132501] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2008] [Indexed: 05/27/2023]
Abstract
High-precision Penning-trap mass measurements of the N approximately Z approximately 34 nuclides 68Se, 70Se, (70m)Br, and 71Br were performed, reaching experimental uncertainties of 0.5-15 keV. The new and improved mass data together with theoretical Coulomb displacement energies were used as input for rp process network calculations. An increase in the effective lifetime of the waiting point nucleus 68Se was found, and more precise information was obtained on the luminosity during a type I x-ray burst along with the final elemental abundances after the burst.
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Affiliation(s)
- J Savory
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, USA.
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12
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Okada K, Wada M, Nakamura T, Takamine A, Lioubimov V, Schury P, Ishida Y, Sonoda T, Ogawa M, Yamazaki Y, Kanai Y, Kojima TM, Yoshida A, Kubo T, Katayama I, Ohtani S, Wollnik H, Schuessler HA. Precision measurement of the hyperfine structure of laser-cooled radioactive 7Be+ ions produced by projectile fragmentation. Phys Rev Lett 2008; 101:212502. [PMID: 19113405 DOI: 10.1103/physrevlett.101.212502] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2008] [Indexed: 05/27/2023]
Abstract
The ground state hyperfine splitting of (7)Be+ has been measured by laser-microwave double-resonance spectroscopy in the online rf trap of RIKEN's slow RI-beam facility. Be ions produced by projectile fragmentation of 13C at approximately 1 GeV were thermalized in a rf ion guide gas cell and subsequently laser cooled in the ion trap to approximately 1 microeV. This 10(15)-fold reduction of the kinetic energy allows precision spectroscopy of these ions. A magnetic hfs constant of A=-742.772 28(43) MHz was measured for 7Be+, from which a nuclear magnetic moment of mu(I)=-1.399 28(2)mu(N) was deduced.
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Affiliation(s)
- K Okada
- Department of Physics, Sophia University, 7-1 Kioicho, Chiyoda, Tokyo 102-8554, Japan
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Block M, Bachelet C, Bollen G, Facina M, Folden CM, Guénaut C, Kwiatkowski AA, Morrissey DJ, Pang GK, Prinke A, Ringle R, Savory J, Schury P, Schwarz S. Discovery of a nuclear isomer in 65Fe with penning trap mass spectrometry. Phys Rev Lett 2008; 100:132501. [PMID: 18517939 DOI: 10.1103/physrevlett.100.132501] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2007] [Revised: 01/10/2008] [Indexed: 05/26/2023]
Abstract
A new long-lived isomeric state in (65)Fe has been discovered with Penning trap mass spectrometry and high-precision mass measurements of the neutron-rich isotopes (63-65)Fe and (64-66)Co have been performed with the Low-Energy Beam and Ion Trap Facility at the NSCL. For the new isomer in (65)Fe an excitation energy of 402(5) keV has been determined from the measured mass difference between the isomeric and ground states. The mass uncertainties of all isotopes have been reduced by a factor of 10-100 compared to previous results. In the case of (64)Co the previous mass value was found to deviate by about 5 standard deviations from the new measurement.
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Affiliation(s)
- M Block
- National Superconducting Cyclotron Laboratory (NSCL), Michigan State University, East Lansing, Michigan, USA.
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Bollen G, Davies D, Facina M, Huikari J, Kwan E, Lofy PA, Morrissey DJ, Prinke A, Ringle R, Savory J, Schury P, Schwarz S, Sumithrarachchi C, Sun T, Weissman L. Experiments with thermalized rare isotope beams from projectile fragmentation: a precision mass measurement of the superallowed beta emitter 38Ca. Phys Rev Lett 2006; 96:152501. [PMID: 16712152 DOI: 10.1103/physrevlett.96.152501] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2006] [Indexed: 05/09/2023]
Abstract
The mass of the short-lived radio nuclide 38Ca (T(1/2) = 440 ms) has been measured with the 9.4-T Penning trap mass spectrometer of the Low-Energy Beam and Ion Trap Facility. A mass uncertainty of deltam = 280 eV has been achieved, corresponding to deltam/m = 8 x 10(-9). The result makes 38Ca, a superallowed beta emitter, a new candidate to test the conserved-vector-current hypothesis. The experiment is also the first demonstration that short-lived radioactive isotopes produced by projectile fragmentation of relativistic heavy-ion beams can be slowed down and prepared such that precision experiments of this kind are possible.
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Affiliation(s)
- G Bollen
- National Superconducting Cyclotron Laboratory. Michigan State University, East Lansing, Michigan, USA.
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