Study for halo-nuclei by mass measurements in storage-ring

• Project/Area Number: 18H03695
• Research Category: Grant-in-Aid for Scientific Research (A)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Medium-sized Section 15:Particle-, nuclear-, astro-physics, and related fields
• Research Institution: University of Tsukuba
• Principal Investigator: Ozawa Akira 筑波大学, 数理物質系, 教授 (80260214)
• Co-Investigator(Kenkyū-buntansha): 山口 由高 国立研究開発法人理化学研究所, 仁科加速器科学研究センター, 技師 (40415328)
• Project Period (FY): 2018-04-01 – 2021-03-31
• Project Status: Completed (Fiscal Year 2020)
• Budget Amount: ¥45,760,000 (Direct Cost: ¥35,200,000、Indirect Cost: ¥10,560,000); Fiscal Year 2020: ¥4,290,000 (Direct Cost: ¥3,300,000、Indirect Cost: ¥990,000); Fiscal Year 2019: ¥5,330,000 (Direct Cost: ¥4,100,000、Indirect Cost: ¥1,230,000); Fiscal Year 2018: ¥36,140,000 (Direct Cost: ¥27,800,000、Indirect Cost: ¥8,340,000)
• Keywords: 原子核の質量 / 蓄積リング / 不安定核 / 質量測定

Outline of Final Research Achievements

RI Beam Factory in RIKEN (RIBF) is presently most intense unstable nuclear beam facility in the world. Rare-RI Ring (R3) in RIBF is motivated by mass measurements for unstable nuclei, that are located very far from the stability. R3 is operated from FY 2015. However, since R3 is shortly after the operation, accuracy for mass measurements was insufficient. In this research, we upgraded kicker magnets in R3 and detectors for mass measurements. Thus, we could increase the accuracy. Hereafter we will perform precise mass measurements for unstable nuclei in R3.

Academic Significance and Societal Importance of the Research Achievements

不安定核の蓄積リングは、質量測定だけでなく、寿命測定を行うことができる。また、多価イオンを蓄積できるので、多価状態のベータ崩壊など、通常とは異なる物理現象の観測も可能になる。理研RIビームファクトリー(RIBF)は、現在、世界最強のRIビーム施設であり、ハロー原子核を含む安定線から遠く離れた不安定核を数多く作ることができる。本研究により、RIBFの蓄積リングをアップグレードしたことで、RIBFでの不安定核研究をより高めることに貢献した。

Research Products

• [Int'l Joint Research] IMP(中国)
• [Int'l Joint Research] GSI(ドイツ)
• [Int'l Joint Research] IMP(中国)
• [Int'l Joint Research] GSI(ドイツ)
• [Int'l Joint Research] IMP(中国)
• [Int'l Joint Research] GSI(ドイツ)
• [Journal Article] Development and operation of a time-of-flight detector to confirm particle storage at the Rare-RI Ring (2021)
  • Author(s): D. Nagae et al.
  • Journal Title: Nuclear Inst. and Methods in Physics Research, A Volume: 986 Pages: 164713-164713
  • DOI: 10.1016/j.nima.2020.164713
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Experimental Challenges of the First Mass Measurement Campaign at the Rare-RI Ring (2020)
  • Author(s): S. Naimi et al.
  • Journal Title: Journal of Physics: Conference Series Volume: 1643 Issue: 1 Pages: 012058-012058
  • DOI: 10.1088/1742-6596/1643/1/012058
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Mass measurements for the Tz = －2 fp-shell nuclei 40Ti, 44Cr, 46Mn, 48Fe, 50Co, and 52Ni (2020)
  • Author(s): C. Y. Fu, Y. H. Zhang M. Wang, X. H. Zhou, Yu. A. Litvinov, K. Blaum, H. S. Xu, X. Xu, P. Shuai, Y. H. Lam, R. J. Chen, X. L. Yan, X. C. Chen, J. J. He, S. Kubono, M. Z. Sun, X. L. Tu, Y. M. Xing, Q. Zeng, X. Zhou, W. L. Zhan, S. Litvinov, G. Audi, T. Uesaka, T. Yamaguchi, A. Ozawa, B. H. Sun, Y. Sun, F. R. Xu,
  • Journal Title: Phys. Rev. C Volume: 102 Issue: 5 Pages: 054311-054311
  • DOI: 10.1103/physrevc.102.054311
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Masses of ground and isomeric states of 101In and configuration-dependent shell evolution in odd-A indium isotopes (2019)
  • Author(s): X. Xu, J. H. Liu, C. X. Yuan, Y. M. Xing, M. Wang, Y. H. Zhang, X. H. Zhou, Yu. A. Litvinov, K. Blaum, R. J. Chen, et al.
  • Journal Title: Phys. Rev. C Volume: 100 Issue: 5 Pages: 051303-051303
  • DOI: 10.1103/physrevc.100.051303
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Masses of neutron-rich 52-54Sc and 54,56Ti nuclides: The N = 32 subshell closure in scandium (2019)
  • Author(s): X. Xu, M. Wang, K. Blaum, J. D. Holt, Yu. A. Litvinov, A. Schwenk, J. Simonis, S. R. Stroberg, Y. H. Zhang, H. S. Xu, et l.
  • Journal Title: Phys. Rev. C Volume: 99 Issue: 6 Pages: 064303-064303
  • DOI: 10.1103/physrevc.99.064303
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] First Direct Mass Measurements of Nuclides around Z=100 with a Multireflection Time-of-Flight Mass Spectrograph (2018)
  • Author(s): 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 J.?Y.、Morimoto K.、Morita K.、Mukai M.、Murray I.、Niwase T.、Okada K.、Ozawa A.、Rosenbusch M.、Takamine A.、Tanaka T.、Watanabe Y.?X.、Wollnik H.、Yamaki S.
  • Journal Title: Physical Review Letters Volume: 120 Issue: 15 Pages: 152501-152501
  • DOI: 10.1103/physrevlett.120.152501
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Isochronous mass measurements of Tz = -1 fp-shell nuclei from projectile fragmentation of 58Ni (2018)
  • Author(s): Y. H. Zhang, P. Zhang, X. H. Zhou, M. Wang, Yu. A. Litvinov, H. S. Xu, X. Xu, P. Shuai, Y. H. Lam, R. J. Chen, et al.
  • Journal Title: Phys. Rev. C Volume: 98 Issue: 1 Pages: 014319-014319
  • DOI: 10.1103/physrevc.98.014319
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Mass measurements of neutron-deficient Y, Zr, and Nb isotopes and their impact on rp and νp nucleosynthesis processes (2018)
  • Author(s): Y.M. Xing, K.A. Li, Y.H. Zhang, X.H. Zhou, M. Wang, Yu.A. Litvinov, K. Blaum, S. Wanajo, S. Kubono, G. Martinez-Pinedo, et al.
  • Journal Title: Phys. Lett. B Volume: 781 Pages: 358-363
  • DOI: 10.1016/j.physletb.2018.04.009
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] New mass anchor points for neutron-deficient heavy nuclei from direct mass measurements of radium and actinium isotopes (2018)
  • Author(s): M. Rosenbusch, Y. Ito, P. Schury, M. Wada, D. Kaji, K. Morimoto, H. Haba, S. Kimura, H. Koura, M. MacCormick, H. Miyatake, J. Y. Moon, K. Morita, I. Murray, T. Niwase, A. Ozawa, M. Reponen, A. Takamine, T. Tanaka, and H. Wollnik
  • Journal Title: Phys. Rev. C Volume: 97 Issue: 6 Pages: 064306-064306
  • DOI: 10.1103/physrevc.97.064306
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Masses of the Tz = －3/2 nuclei 27P and 29S (2018)
  • Author(s): C. Y. Fu, Y. H. Zhang, X. H. Zhou, M. Wang, Yu. A. Litvinov, K. Blaum, H. S. Xu, X. Xu, P. Shuai, Y. H. Lam, et al.
  • Journal Title: Phys. Rev. C Volume: 98 Issue: 1 Pages: 014315-014315
  • DOI: 10.1103/physrevc.98.014315
  • Peer Reviewed / Int'l Joint Research
• [Presentation] Present status of Rare-RI Ring (R3) and mass measurements (2020)
  • Author(s): A. Ozawa
  • Organizer: RIBF Users Meeting 2020
  • Int'l Joint Research / Invited
• [Presentation] Mass measurements for Ni-isotopes in Rare-RI Ring, RIBF (2019)
  • Author(s): A. Ozawa
  • Organizer: hina-Japan Collaboration Workshop on “Nuclear Mass and Life for Unraveling Mysteries of R-process”
  • Int'l Joint Research / Invited
• [Presentation] Mass measurements in Rare-RI Ring in RIBF (2018)
  • Author(s): A. Ozawa
  • Organizer: Workshop on “Physics at HIAF High-Energy Beam Lines”