Feasibility study on storage-ring spectrometry of superheavy elements

• Project/Area Number: 16K13799
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Particle/Nuclear/Cosmic ray/Astro physics
• Research Institution: Saitama University
• Principal Investigator: Yamaguchi Takayuki 埼玉大学, 理工学研究科, 准教授 (10375595)
• Research Collaborator: MORIMOTO Koji 理化学研究所, 仁科加速器科学研究センター, チームリーダー (00332247) ; NISHIMURO Kunimitsu 埼玉大学, 理工学研究科, 大学院生
• Project Period (FY): 2016-04-01 – 2019-03-31
• Project Status: Completed (Fiscal Year 2018)
• Budget Amount: ¥3,770,000 (Direct Cost: ¥2,900,000、Indirect Cost: ¥870,000); Fiscal Year 2018: ¥1,170,000 (Direct Cost: ¥900,000、Indirect Cost: ¥270,000); Fiscal Year 2017: ¥1,950,000 (Direct Cost: ¥1,500,000、Indirect Cost: ¥450,000); Fiscal Year 2016: ¥650,000 (Direct Cost: ¥500,000、Indirect Cost: ¥150,000)
• Keywords: 実験核物理 / ショットキーピックアップ / イオン蓄積リング

Outline of Final Research Achievements

The present study aims at developing a new particle identification technique for superheavy elements. When they are stored in a storage ring, they can be unambiguously identified using the Schottky-pickup technique, even for a single ion. This could be a new direction for a series of new elements synthesis experiments. To realize such experiments, feasibility studies were conducted; we performed realistic three-dimensional electromagnetic field simulations to design a high-sensitive and compact Schottky cavity, and fabricated a prototype. As the results of offline tests, we obtained the sensitivity that a proton could be detected within 1.5 sec, that is good enough for the present purpose.

Academic Significance and Societal Importance of the Research Achievements

理研加速器の大強度ビームと気体充填型反跳分離装置GARISを用いた10年以上にもおよぶ長期実験において、原子番号113番元素が合成され、ニホニウムと命名されるに至った。この実験ではニホニウムからα崩壊連鎖して放出されるα粒子の相関を用いて、合成が証明された。しかし、今後の新元素探索に於いて合成確率が下がること、また、崩壊中に核分裂する確率があることから、新しい識別方法が望まれている。本研究では蓄積リング中に周回させた新元素を1粒子から同定するショットキーピックアップ法の開発を行った。開発したショットキーでは約1.5秒で陽子1個を識別できるため、新しい新元素合成実験に向けて応用が期待される。

Research Products

• [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] 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
• [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] Determination of fusion barrie distributions from quasielastic scattering cross sections towards superheavy nuclei synthesis (2018)
  • Author(s): T. Tanaka, Y. Narikiyo, K. Morita, K. Fujita, D. Kaji, K. Morimoto, S. Yamaki, Y. Wakabayashi, K. Tanaka, M. Takeyama, et al.
  • Journal Title: J. Phys. Soc. Jpn. Volume: 87 Issue: 1 Pages: 014201-014201
  • DOI: 10.7566/jpsj.87.014201
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Nuclear-matter radius studies from 58Ni(α,α) experiments at the GSI Experimental Storage Ring with the EXL facility (2017)
  • Author(s): J. C. Zamora, T. Aumann, S. Bagchi, S. Boenig, M. Csatlos, I. Dillmann, C. Dimopoulou, P. Egelhof, V. Eremin, T. Furuno, et al.
  • Journal Title: Phys. Rev. C Volume: 96 Issue: 3 Pages: 034617-034617
  • DOI: 10.1103/physrevc.96.034617
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Half-life measurement of short-lived 94mRu44+ using isochronous mass spectrometry (2017)
  • Author(s): Q. Zeng, M. Wang, X. H. Zhou, Y. H. Zhang, X. L. Tu, X. C. Chen, X. Xu, Yu. A. Litvinov, H. S. Xu, K. Blaum, et al.
  • Journal Title: Phys. Rev. C Volume: 96 Issue: 3 Pages: 031303-031303
  • DOI: 10.1103/physrevc.96.031303
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Application of isochronous mass spectrometry for the study of angular momentum population in projectile fragmentation reactions (2017)
  • Author(s): X. L. Tu, A. Kelic-Heil, Yu. A. Litvinov, Zs. Podolyak, Y. H. Zhang, W. J. Huang, H. S. Xu, K. Blaum, F. Bosch, R. J. Chen, et al.
  • Journal Title: Phys. Rev. C Volume: 95 Issue: 1 Pages: 014610-014610
  • DOI: 10.1103/physrevc.95.014610
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] High-precision QEC values of super allowed 0+ -> 0+ b-emitters 46Cr, 50Fe, and 54Ni (2017)
  • Author(s): P. Zhang, X. Xu, P. Shuai, R.J. Chen, X.L. Yan, Y.H. Zhang, M. Wang, Yu.A. Litvinov, K. Blaum, H.S. Xu, et al.
  • Journal Title: Phys. Lett. B Volume: 767 Pages: 20-24
  • DOI: 10.1016/j.physletb.2017.01.039
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Study of the reaction 48Ca + 248Cm → 296Lv* at RIKEN-GARIS (2017)
  • Author(s): D. Kaji, K. Morita, K. Morimoto, H. Haba, M. Asai, K. Fujita, Z. Gan, H. Geissel, H. Hasebe, S. Hofmann, M. Huang, Y. Komori, L. Ma, J. Maurer, M. Murakami, M. Takeyama, F. Tokanai, T. Tanaka, Y. Wakabayashi, T. Yamaguchi, S. Yamaki, and A. Yoshida
  • Journal Title: J. Phys. Soc. Jpn. Volume: 86 Issue: 3 Pages: 034201-034201
  • DOI: 10.7566/jpsj.86.034201
  • NAID: 210000134293
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] First direct mass measurements of stored neutron-rich 129,130,131Cd isotopes with FRS-ESR (2016)
  • Author(s): R. Knoebel, M. Diwisch, F. Bosch, D. Boutin, L. Chen, C. Dimopoulou, A. Dolinskii, B. Franczak, B. Franzke, H. Geissel, et al.
  • Journal Title: Phys. Lett. B Volume: 754 Pages: 288-293
  • DOI: 10.1016/j.physletb.2016.01.039
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] New results from isochronous mass measurements of neutron-rich uranium fission fragments with the FRS-ESR-facility at GSI (2016)
  • Author(s): R. Knoebel, M. Diwisch, H. Geissel, Yu. A. Litvinov, Z. Patyk, W. R. Plass, C. Scheidenberger, B. Sun, H. Weick, F. Bosch, et al.
  • Journal Title: Eur. Phys. J. A Volume: 52 Issue: 5 Pages: 138-148
  • DOI: 10.1140/epja/i2016-16138-6
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] First measurement of isoscalar giant resonances in a stored-beam experiment (2016)
  • Author(s): J. C. Zamora, T. Furuno et al.
  • Journal Title: Physics Letters B Volume: 763 Pages: 16-19
  • DOI: 10.1016/j.physletb.2016.10.015
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Identification of the lowest T=2, Jpi =0 + isobaric analog state in 52Co and its impact on the understanding of b-decay properties of 52Ni (2016)
  • Author(s): X. Xu, P. Zhang, P. Shuai, R. J. Chen, X. L. Yan, Y. H. Zhang, M. Wang, Yu. A. Litvinov, H. S. Xu, T. Bao, et al.
  • Journal Title: Phys. Rev. Lett. Volume: 117 Issue: 18
  • DOI: 10.1103/physrevlett.117.182503
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] R&D status of pulse shape analysis for short-lived decay of superheavy elements in GARIS-II (2016)
  • Author(s): S. Yamaki, K. Morimoto, D. Kaji, Y. Wakabayashi, M. Takeyama, K. Tanaka, T. Tanaka, H. Baba, T. Yamaguchi, T. Suzuki, K. Morita,
  • Journal Title: Physical Sciences and Technology Volume: 3 Pages: 12-16
  • Peer Reviewed
• [Presentation] Rare-RI Ring project in RIKEN and a proposal at CSRe (2018)
  • Author(s): T. Yamaguchi
  • Organizer: Symposium on Precision Physics Experiments with Stored Highly Charged Ions at Low Energies
  • Int'l Joint Research / Invited
• [Presentation] Rare-RI Ring at RIKEN present status (2017)
  • Author(s): T. Yamaguchi
  • Organizer: NUSTAR annual meeting 2017
  • Place of Presentation: GSI（ドイツ連邦共和国・ダルムシュタット）
  • Year and Date: 2017-02-27
  • Int'l Joint Research / Invited
• [Presentation] Storage-ring mass spectrometry of exotic nuclei (2017)
  • Author(s): T. Yamaguchi
  • Organizer: International symposium on RI beam physics in the 21st century: 10th anniversary of RIBF (RIKEN, Wako, Japan)
  • Int'l Joint Research / Invited
• [Presentation] ILIMA project: isomeric beams, lifetimes and masses at the FAIR storage rings (2017)
  • Author(s): T. Yamaguchi
  • Organizer: 10th International Conference on Nuclear Physics at Storage Rings (Kanazawa, Japan)
  • Int'l Joint Research / Invited
• [Presentation] ILIMA status report (2017)
  • Author(s): T. Yamaguchi
  • Organizer: NUSTAR week 2017 (Ljubljana, Slovenia)
  • Int'l Joint Research / Invited
• [Presentation] RI beam experiments with storage rings -present and future- (2016)
  • Author(s): T. Yamaguchi
  • Organizer: 藤原セミナー
  • Place of Presentation: 下田東急ホテル（静岡県・下田市）
  • Year and Date: 2016-07-06
  • Int'l Joint Research / Invited
• [Presentation] R&D status on pulse shape analysis for short-lived decay of superheavy elements in GARIS-II (2016)
  • Author(s): S. Yamaki
  • Organizer: III International workshop Nuclear physics and astrophysics
  • Place of Presentation: AL-FARABI KAZAKH NATIONAL UNIVERSITY（カザフスタン共和国・アルマトイ）
  • Year and Date: 2016-04-14
  • Int'l Joint Research