Development of tritium target and search for three-neutron states

• Project/Area Number: 17H04833
• Research Category: Grant-in-Aid for Young Scientists (A)
• Allocation Type: Single-year Grants
• Research Field: Particle/Nuclear/Cosmic ray/Astro physics
• Research Institution: Tohoku University
• Principal Investigator: Miki Kenjiro 東北大学, 理学研究科, 助教 (80727090)
• Project Period (FY): 2017-04-01 – 2021-03-31
• Project Status: Completed (Fiscal Year 2020)
• Budget Amount: ¥24,960,000 (Direct Cost: ¥19,200,000、Indirect Cost: ¥5,760,000); Fiscal Year 2019: ¥1,170,000 (Direct Cost: ¥900,000、Indirect Cost: ¥270,000); Fiscal Year 2018: ¥13,260,000 (Direct Cost: ¥10,200,000、Indirect Cost: ¥3,060,000); Fiscal Year 2017: ¥9,750,000 (Direct Cost: ¥7,500,000、Indirect Cost: ¥2,250,000)
• Keywords: 多中性子系 / 荷電交換反応 / 三重水素 / 実験核物理 / 中性子多体系

Outline of Final Research Achievements

For understanding the neutron many-body system, we plan to perform the spectroscopy of the three-neutron (3n) system via the 3H(t,3He)3n reaction at the RIKEN RIBF facility. In this project, we have developed the tritiated titanium target and also the detectors which are necessary for the experiment. We have also performed the 3He(3He,t)3p experiment at the RCNP facility in Osaka University for the spectroscopy of three-proton (3p) system. We have obtained insights into the configuration of the 3p system, and have also made a better estimation of the reaction probability for the 3n experiment.

Academic Significance and Societal Importance of the Research Achievements

中性子多体系を理解することは、原子核物理学の重要課題である。特に、重元素合成サイトとして近年注目を集める中性子星の構造や、2016年に報告された四中性子共鳴状態候補について解釈を行う上でも、基礎的な実験データが必要とされてきた。本研究により三重水素標的の開発とその利用に目途が立ったことで、今後中性子多体系の中でも基礎的な三中性子系の核分光を実現し、理解を深める道筋が出来上がった。また本研究により、RIBF施設の大強度RIビームと三重水素標的を組み合わせる新たな実験の可能性が開拓された。

Research Products

• [Int'l Joint Research] NSCL, Michigan State University/Oak Ridge National Laboratory(米国)
• [Int'l Joint Research] NSCL, Michigan State University/Oak Ridge National Laboratory(米国)
• [Journal Article] Gamow-Teller transitions to Zr93 via the Nb93(t,He3+γ) reaction at 115 MeV/u and its application to the stellar electron-capture rates (2020)
  • Author(s): Gao B.、Zegers R. G. T.、Zamora J. C.、Bazin D.、Brown B. A.、Bender P.、Crawford H. L.、Engel J.、Falduto A.、Gade A.、Gastis P.、Ginter T.、Guess C. J.、Lipschutz S.、Macchiavelli A. O.、Miki K.、Ney E. M.、Longfellow B.、Noji S.、Pereira J.、Schmitt J.、Sullivan C.、Titus R.、Weisshaar D.
  • Journal Title: Physical Review C Volume: 101, 014308 Issue: 1 Pages: 1-10
  • DOI: 10.1103/physrevc.101.014308
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Excitation and $ \gamma$γ-decay coincidence measurements at the GRAF beamline for studies of pygmy and giant dipole resonances (2019)
  • Author(s): Kobayashi N.、Miki K.、Hashimoto T.、Iwamoto C.、Tamii A.、Aoi N.、Carpenter M. P.、Hatanaka K.、Isaak J.、Ideguchi E.、Morinobu S.、Nakamura S.、Noji S.
  • Journal Title: The European Physical Journal A Volume: 55 Issue: 12 Pages: 1-13
  • DOI: 10.1140/epja/i2019-12854-7
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Experimental constraint on stellar electron-capture rates from the Sr88(t,He3+γ)Rb88 reaction at 115 MeV/u (2019)
  • Author(s): Zamora J. C.、Zegers R. G. T.、Austin Sam M.、Bazin D.、Brown B. A.、Bender P. C.、Crawford H. L.、Engel J.、Falduto A.、Gade A.、Gastis P.、Gao B.、Ginter T.、Guess C. J.、Lipschutz S.、Longfellow B.、Macchiavelli A. O.、Miki K.、Ney E.、Noji S.、Pereira J.、Schmitt J.、Sullivan C.、Titus R.、Weisshaar D.
  • Journal Title: Physical Review C Volume: 100, 032801(R) Issue: 3 Pages: 1-6
  • DOI: 10.1103/physrevc.100.032801
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Isovector excitations in 100 Nb and their decays by neutron emission studied via theMo100(t,He3+n)reaction at 115 MeV/ u (2017)
  • Author(s): Miki K.、Zegers R.G.T.、Austin Sam M.、Bazin D.、Brown B.A.、Dombos A.C.、Grzywacz R.K.、Harakeh M.N.、Kwan E.、Liddick S.N.、Lipschutz S.、Litvinova E.、Madurga M.、Mustonen M.T.、Ong W.J.、Paulauskas S.V.、Perdikakis G.、Pereira J.、Peters W.A.、Robin C.、Scott M.、Spyrou A.、Sullivan C.、Titus R.
  • Journal Title: Physics Letters B Volume: 769 Pages: 339-344
  • DOI: 10.1016/j.physletb.2017.04.004
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Presentation] RIBFにおける3H(t,3He)3n実験に向けた装置開発 (2021)
  • Author(s): 亀谷晃毅, 宇津城雄大, 三木謙二郎, NP1712-SHARAQ11 collaboration
  • Organizer: 日本物理学会第76回年次大会
• [Presentation] RIBF実験に用いる三重水素吸蔵チタン標的の実作 (2021)
  • Author(s): 宇津城雄大, 三木謙二郎, 亀谷晃毅, 北山翔, 齋藤由子, 丸田祥輝, 今井伸明, 上坂友洋, 梅津裕生, 波多野雄治, 原正憲
  • Organizer: 日本物理学会第76回年次大会
• [Presentation] Experimental studies on multi-neutron and proton systems, and Tritium target for RIBF (2021)
  • Author(s): Kenjiro Miki
  • Organizer: The 8th Asia-Pacific Conference on Few-Body Problems in Physics
  • Int'l Joint Research / Invited
• [Presentation] 三中性子系核分光のための3H(t,3He)3n実験計画の現状 (2020)
  • Author(s): 齋藤由子, 三木謙二郎, 宇津城雄大, 酒井大輔, 井上南, 今井伸明, 上坂友洋, 梅津裕生, 波多野雄治, 廣瀬耀, Kathrin Wimmer, 道正新一郎
  • Organizer: 日本物理学会第75回年次大会
• [Presentation] RIBFにおける3H(t,3He)3n反応測定の為の三重水素標的開発(2) (2019)
  • Author(s): 宇津城雄大、三木謙二郎
  • Organizer: 日本物理学会2019年秋季大会
• [Presentation] 3He(3He,t)3p反応による三陽子系の核分光 (2019)
  • Author(s): 酒井大輔、三木謙二郎
  • Organizer: 日本物理学会第74回年次大会
• [Presentation] Development of tritium target for the 3H(t,3He)3n experiment at RIBF (2019)
  • Author(s): Kenjiro Miki
  • Organizer: OEDO collaboratiom meeting
  • Int'l Joint Research / Invited
• [Presentation] Development of tritium target for the 3H(t,3He)3n experiment at RIBF (2019)
  • Author(s): K. Miki
  • Organizer: Workshop on Gas-filled Detectors and Systems (GDS): Rare-gas target handling and recycling systems
  • Int'l Joint Research / Invited
• [Presentation] RIBFにおける3H(t,3He)3n反応測定の為の三重水素標的開発 (2019)
  • Author(s): 三木謙二郎
  • Organizer: 日本物理学会第74回年次大会
• [Presentation] 三中性子共鳴探索実験の為のMWDC開発 (2019)
  • Author(s): 宇津城雄大、三木謙二郎
  • Organizer: 日本物理学会第74回年次大会
• [Presentation] 三中性子状態観測の為の三重水素標的の検討 (2018)
  • Author(s): 酒井大輔
  • Organizer: 日本物理学会第73回年次大会