Charge symmetry breaking in Lambda-N interaction investigated via hypernuclear gamma-ray spectroscopy

• Project/Area Number: 15H02079
• Research Category: Grant-in-Aid for Scientific Research (A)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Particle/Nuclear/Cosmic ray/Astro physics
• Research Institution: Tohoku University
• Principal Investigator: Tamura Hirokazu 東北大学, 理学研究科, 教授 (10192642)
• Project Period (FY): 2015-04-01 – 2019-03-31
• Project Status: Completed (Fiscal Year 2019)
• Budget Amount: ¥41,990,000 (Direct Cost: ¥32,300,000、Indirect Cost: ¥9,690,000); Fiscal Year 2018: ¥4,290,000 (Direct Cost: ¥3,300,000、Indirect Cost: ¥990,000); Fiscal Year 2017: ¥12,480,000 (Direct Cost: ¥9,600,000、Indirect Cost: ¥2,880,000); Fiscal Year 2016: ¥12,610,000 (Direct Cost: ¥9,700,000、Indirect Cost: ¥2,910,000); Fiscal Year 2015: ¥12,610,000 (Direct Cost: ¥9,700,000、Indirect Cost: ¥2,910,000)
• Keywords: 原子核物理学 / ハイパー核 / ガンマ線分光 / ストレンジネス / 荷電対称性 / ゲルマニウム検出器 / バリオン間相互作用 / 実験核物理 / 荷電対称性の破れ / 鏡像核 / J-PARC

Outline of Final Research Achievements

This subject aims at precisely measuring γ-rays in 4ΛHe and 4ΛH hypernuclei and comparing their level structure to clarify a possible large charge symmetry breaking (CSB) effect in light Λ hypernuclei suggested by old experiments. We carried out a 4ΛHe experiment and oberved a γ-ray at 1.406 MeV. It is much larger than the corresponding energy for 4ΛH, 1.09 MeV. Thus we clearly confirmed the existence of a very large CSB effect. In order to measure the 4ΛH γ-ray again but much precisely with a new beam line at J-PARC, we have developed all the detectors including a new fiber tracking detector and made the experiment ready to run.

Academic Significance and Societal Importance of the Research Achievements

荷電対称性とは、原子核の陽子と中性子の間の対称性で、その破れは極めて小さい。今回の実験により、これがΛハイパー核では非常に大きくなることが初めて確定した。これは原子核物理学の基本的概念を揺さぶる重要な発見である。この大きな破れの起源は、さまざまな努力にもかかわらずまだ理論的に説明できないが、この発見を機に理論研究が大きく進展すると期待される。荷電対称性の破れは、uクォークとdクォークの小さな質量差を起源としているため、それがどのようにバリオン間相互作用に反映されるのかが明らかになれば、核力を含むバリオン間相互作用のより本質的な理解につながるであろう。

Research Products

• [Int'l Joint Research] ソウル国立大学校(韓国)
• [Int'l Joint Research] INFN, Torino(イタリア)
• [Int'l Joint Research] INFN, Sezione di Torino(イタリア)
• [Int'l Joint Research] Seoul National University/Korea University(韓国)
• [Int'l Joint Research] Joint Institute for Nuclear Research(ロシア連邦)
• [Int'l Joint Research] Beihang University(中国)
• [Int'l Joint Research] ソウル国立大学/高麗大学(韓国)
• [Int'l Joint Research] INFN トリノ(イタリア)
• [Int'l Joint Research] Seoul National University(韓国)
• [Int'l Joint Research] INFN, Sezione di Torino/Universit di Torino/Politecnico di Torino(イタリア)
• [Int'l Joint Research] Joint Institute for Nuclear Research(ロシア連邦)
• [Journal Article] Future Possibilities for Accelerators in Nuclear Physics (2019)
  • Author(s): Shoji Nagamiya, Hideto En'yo, Hirokazu Tamura
  • Journal Title: Rev. Accel. Sci. Tech. Volume: 10 Pages: 13-13
  • DOI: 10.1142/9789811209604_0003
  • ISBN: 9789811209598, 9789811209604
  • Peer Reviewed
• [Journal Article] Present status and prospect of nuclear physics with strangeness --summary of HYP2018 (2019)
  • Author(s): H. Tamura
  • Journal Title: AIP Conference Proceedings Volume: 2130 Pages: 60001-60001
  • DOI: 10.1063/1.5118419
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Gamma-ray spectroscopy of single Λ-hypernuclei at J-PARC: Results and perspective (2019)
  • Author(s): T. Koike, T. Nagae, T. Takahashi, H. Tamura et al.
  • Journal Title: AIP Conference Proceedings Volume: 2130 Pages: 20011-20011
  • DOI: 10.1063/1.5118379
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Strangeness Nuclear Physics (2019)
  • Author(s): H. Tamura
  • Journal Title: JPS Conference Proceedings Volume: 26 Pages: 11003-11003
  • DOI: 10.7566/jpscp.26.011003
  • Peer Reviewed / Open Access
• [Journal Article] First γ-Ray Spectroscopy of an sd-Shell Hypernucleus, 19ΛF (2019)
  • Author(s): S.B. Yang T. Nagae, T. Takahashi, H. Tamura et al.
  • Journal Title: JPS Conference Proceedings Volume: 26 Pages: 23015-23015
  • DOI: 10.7566/jpscp.26.023015
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Search for Excited State of \(_{\Sigma }^{4}\text{He}\) Hypernucleus in the J-PARC E13 Experiment (2019)
  • Author(s): M. Nakagawa、S. Nagao et al.
  • Journal Title: JPS Conference Proceedings Volume: 26 Pages: 023005-023005
  • DOI: 10.7566/jpscp.26.023005
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] The First Determination of the Level Structure ofan sd-shell Hypernucleus 19F(Lambda) (2018)
  • Author(s): S.B.Yang, S.Hasegawa, K.Imai et al.,
  • Journal Title: Phys. Rev. Lett. Volume: 120 Issue: 13 Pages: 132505-132505
  • DOI: 10.1103/physrevlett.120.132505
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Gamma-ray spectroscopy of hypernuclei -Recent results and prospect at J-PARC- (2017)
  • Author(s): H. Tamura, T. O. Yamamoto, M. Agnello, Y. Akazawa, N. Amano, K. Aoki, E. Botta, N. Chiga, H. Ekawa, P. Evtoukhovitch, A. Feliciello, M. Fujita, T. Gogami, S. Hasegawa, S. H. Hayakawa, T. Hayakawa, R. Honda K. Hosomi, ... T. Koike, ... K. Miwa, ...T. Takahashi et al.
  • Journal Title: JPS Conference Proceedings Volume: 17 Pages: 011004-011004
  • DOI: 10.7566/jpscp.17.011004
  • Peer Reviewed / Open Access / Int'l Joint Research / Acknowledgement Compliant
• [Journal Article] The First Gamma-ray Spectroscopic Study of sd-shell Hypernucleus, 19ΛF (2017)
  • Author(s): S.B. Yang, M. Agnello, Y. Akazawa, N. Amano, K. Aoki, E. Botta, N. Chiga, H. Ekawa, P. Evtoukhovitch, A. Feliciello, M. Fujita, T. Gogami, S. Hasegawa, S. H. Hayakawa, T. Hayakawa, R. Honda K. Hosomi, ... T. Koike, ... K. Miwa, ... T. Takahashi, H. Tamura et al. (J-PARC E13 collaboration)
  • Journal Title: JPS Conference Proceedings Volume: 17 Pages: 012004-012004
  • DOI: 10.7566/jpscp.17.012004
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Search for Excited State of Sigma Hypernucleus in the J-PARC E13 Experiment (2017)
  • Author(s): M. Nakagawa, M. Agnello, Y. Akazawa, N. Amano, K. Aoki, E. Botta, N. Chiga, H. Ekawa, P. Evtoukhovitch, A. Feliciello, M. Fujita, T. Gogami, S. Hasegawa, S. H. Hayakawa, T. Hayakawa, R. Honda, K. Hosomi,... T. Koike, ... K. Miwa, ...T. Takahashi, H. Tamura et al.
  • Journal Title: JPS Conference Proceedings Volume: 17 Pages: 0120091-4
  • DOI: 10.7566/jpscp.17.012009
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Reopening of Research Activities on Strangeness Nuclear Physics at J-PARC (2017)
  • Author(s): Kazuhiro Tanaka, Hirokazu Tamura
  • Journal Title: Nuclear Physics News Volume: 27 Issue: 2 Pages: 21-27
  • DOI: 10.1080/10619127.2017.1315285
  • Peer Reviewed / Open Access
• [Journal Article] Missing-mass spectroscopy with the 6Li(π-,K+)X reaction to search for 6ΛH (2017)
  • Author(s): R. Honda, T. Koike, K. Miwa, A. Sakaguchi, H. Tamura, M. Ukai, T. Yamamoto et al.
  • Journal Title: Phys. Rev. C Volume: 96 Issue: 1 Pages: 014005-014005
  • DOI: 10.1103/physrevc.96.014005
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Observation of Spin-Dependent Charge Symmetry Breaking in ΛN Interaction: Gamma-ray Spectroscopy of 4-Lambda-He (2015)
  • Author(s): T. O. Yamamoto, M. Agnello, Y. Akazawa, N. Amano, K. Aoki, E. Botta, N. Chiga, H. Ekawa, P. Evtoukhovitch, A. Feliciello, M. Fujita, T. Gogami, S. Hasegawa, S. H. Hayakawa, T. Hayakawa, R. Honda, K. Hosomi, S. H. Hwang, N. Ichige, Y. Ichikawa, et al.
  • Journal Title: Physical Review Letters Volume: 115 Issue: 22 Pages: 222501-222501
  • DOI: 10.1103/physrevlett.115.222501
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Study of ΛN Interaction via the γ-ray Spectroscopy of 4ΛHe and 19ΛFe (E13-1st) (2015)
  • Author(s): T.O. Yamamoto, M. Agnello, Y. Akazawa, N. Amano, K. Aoki, E. Botta, N. Chiga, H. Ekawa, P. Evtoukhovitch, A. Feliciello, M. Fujita, T. Gogami, S. Hasegawa, S.H. Hayakawa, T. Hayakawa, R. Honda, K. Hosomi, ... T. Koike, ... H. Tamura, ... M. Ukai et al
  • Journal Title: JPS Conference Proceedings Volume: 8
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Measurement of the Λ Spin-flip B(M1) Value in Hypernuclei (2015)
  • Author(s): Y. Sasaki, T. Koike, K. Miwa, A. Sakaguchi, H. Tamura et al.
  • Journal Title: JPS Conference Proceedings Volume: 8 Pages: 0220131-4
  • DOI: 10.7566/jpscp.8.022013
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] J-PARC E19 Experiment: Pentaquark Θ+ Search in Hadronic Reaction at J-PARC (2015)
  • Author(s): T.N. Takahashi et al.
  • Journal Title: JPS Conference Proceedings Volume: 8 Pages: 022011-022011
  • DOI: 10.7566/jpscp.8.022011
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Hypernuclear production cross section in the reaction of 6Li + 12C at 2 AGeV (2015)
  • Author(s): C. Rappold, A. Sakaguchi, H. Tamura et al.
  • Journal Title: Physics Letters B Volume: 747 Pages: 129-134
  • DOI: 10.1016/j.physletb.2015.05.059
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Precise determination of 12-Lambda-C level structure by γ-ray spectroscopy (2015)
  • Author(s): Kenji Hosomi, Yue Ma, Shuhei Ajimura, Kanae Aoki, Seishi Dairaku, Yuanyong Fu, Hiroyuki Fujioka, Kenta Futatsukawa, Wataru Imoto, Yutaka Kakiguchi, Masaharu Kawai, Sari Kinoshita, Takeshi Koike, Nayuta Maruyama, Masahiro Mimori, Shizu Minami, Yusuke Miura, Koji Miwa, Yohei Miyagi, Tomofumi Nagae, et al.
  • Journal Title: Progress of Theoretical and Experimental Phyiscs Volume: 081D01 Issue: 8 Pages: 1-8
  • DOI: 10.1093/ptep/ptv113
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Presentation] Experimental studies on possible modification of baryons in nuclei (2020)
  • Author(s): H. Tamura
  • Organizer: International symposium on Clustering as a Window on the Hierarchical Structure of Quantum Systems (CLUSHIQ2020), Beppu, Japan
  • Int'l Joint Research
• [Presentation] Hypernuclear Physics --Recent Results and Future Prospects (2019)
  • Author(s): H. Tamura
  • Organizer: Symposium on Rare Isotope Sciences, Institute for Basic Science, Daejeon, Korea
  • Int'l Joint Research / Invited
• [Presentation] Hypernuclear Physics --How to Solve the Hyperon Puzzle-- (2019)
  • Author(s): H. Tamura
  • Organizer: International Symposium on Nuclear Symmetry Energy (NuSYM2019), Da Nan, Vietnam
  • Int'l Joint Research / Invited
• [Presentation] Hypernuclear Physics at J-PARC (2019)
  • Author(s): H. Tamura
  • Organizer: THEIA-STRONG2020 workshop 2019, Speyer, Germany
  • Int'l Joint Research
• [Presentation] Status and perspective of hypernuclear physics at J-PARC (2019)
  • Author(s): H. Tamura
  • Organizer: 3rd EMMI Workshop: Anti-matter, hyper-matter and exotica production at the LHC, Wroclaw, Poland
  • Int'l Joint Research / Invited
• [Presentation] Possible Modification of a Hyperon in Hypernuclei (2019)
  • Author(s): H. Tamura
  • Organizer: STRANEX: Recent progress and perspectives in STRANge EXotic atoms studies and related topics, ECT*, Trento, Italy
  • Int'l Joint Research
• [Presentation] ハイペロンパズルを解決するために実験屋は何をすべきか？ (2019)
  • Author(s): 田村裕和
  • Organizer: 研究会「高密度ハドロン・クォーク物質の諸相と中性子星の構造・進化」, 京都大学基礎物理学研究所
• [Presentation] J-PARCでの原子核・ハドロン実験 (2019)
  • Author(s): 田村裕和
  • Organizer: 研究会「シミュレーションによる宇宙の基本法則と進化の解明に向けて」(QUCS2019) , 京都大学基礎物理学研究所
  • Invited
• [Presentation] Summary of HYP2018 (2018)
  • Author(s): H. Tamura
  • Organizer: The 13st International Conference on Hypernuclear and Strange Particle Physics (HYP2018), Portsmouth, VA, USA
  • Int'l Joint Research / Invited
• [Presentation] Recent results in Hypernuclear physics (2018)
  • Author(s): H. Tamura
  • Organizer: International School of Nuclear Physics 40th Course “The Strong Interaction: From Quarks and Gluons to Nuclei and Stars”, Erice, Italy
  • Int'l Joint Research
• [Presentation] Gamma-ray spectroscopy of hypernuclei (2018)
  • Author(s): H. Tamura
  • Organizer: International Conference on Physics, Mandalay 2018 (ICPM21018), Mandalay, Myanmar
  • Int'l Joint Research / Invited
• [Presentation] Strangeness Nuclear Physics (2018)
  • Author(s): H. Tamura
  • Organizer: The 8th International Conference on Quarks and Nuclear Physics, Tsukuba
  • Int'l Joint Research / Invited
• [Presentation] ストレンジネス ―この35年とこれから― (2018)
  • Author(s): 田村裕和
  • Organizer: 研究会「ストレンジネス核物理の進展と今後の展望」, フォレスト本郷、東京
  • Invited
• [Presentation] Nuclear Physics with Strangeness (2018)
  • Author(s): H. Tamura
  • Organizer: 56th International Winter Meeting on Nuclear Physics, Bormio, Italy
  • Int'l Joint Research / Invited
• [Presentation] Properties and behavier of baryons in a nucleus studied from precise gamma-spectroscopy and weak decays of Λ hypernuclei (2018)
  • Author(s): H. Tamura
  • Organizer: International Workshop on the Project for the Extended hadron Experimental Facility at J-PARC, Tokai, Japan
  • Int'l Joint Research / Invited
• [Presentation] Hadrons in medium (2017)
  • Author(s): H. Tamura
  • Organizer: The 21st Particle and Nuclei International Conference (PANIC2017), Beijing, China
  • Int'l Joint Research / Invited
• [Presentation] Experimental studies of high density baryonic matter with and without strangeness (2017)
  • Author(s): H. Tamura
  • Organizer: XVII International Conference on Hadron Spectroscopy and Structure (Hadron2017), Salamanca, Spain
  • Int'l Joint Research / Invited
• [Presentation] Prospect for Hypernuclear Studies at J-PARC K1.1 Beam Line (Prospect on S= -1 Hypernuclei) (2017)
  • Author(s): H. Tamura
  • Organizer: “Advances and open problems in low-energy nuclear and hadronic STRAngeness physics” workshop, Trento, Italy
  • Int'l Joint Research / Invited
• [Presentation] Hypernuclear physics with kaon (and pion) beams (2017)
  • Author(s): H. Tamura
  • Organizer: The 2nd EMMI workshop: Anti-matter, hyper-matter, and exotica production at the LHC, Trino, Italy
  • Int'l Joint Research / Invited
• [Presentation] Overview of hypernuclei -What are exciting now? (2016)
  • Author(s): H. Tamura
  • Organizer: EMMI Workshop on anti-matter, hyper-matter and exotica production at the LHC
  • Place of Presentation: CERN, Geneva, Switzerland
  • Year and Date: 2016-07-20
  • Int'l Joint Research / Invited
• [Presentation] Recent Achievements at J-PARC and Future Prospects of Hypernuclear Study (2016)
  • Author(s): H. Tamura
  • Organizer: The Second JLab Hypernuclear Workshop
  • Place of Presentation: Jefferson Laboratory, Newport News, VA, USA
  • Year and Date: 2016-03-14
  • Int'l Joint Research / Invited
• [Presentation] Study of ΛN interaction via the A=4 mirror Λ hypernuclei: H and He (2016)
  • Author(s): T. Koike
  • Organizer: Future directions for nuclear structure and reaction theories: Ab initio approaches for 2020
  • Place of Presentation: GANIL, Caen, France
  • Year and Date: 2016-03-14
  • Int'l Joint Research / Invited
• [Presentation] Present Status and Future Prospectsof Hypernuclear Physicsat J-PARC (2016)
  • Author(s): H. Tamura
  • Organizer: Internation Workshop on "Production and study of neutron-rich hypernucle -.Physics and potentialities at FAIR/R3B"
  • Place of Presentation: CEA-Saclay, Orme des Merisiers, France
  • Year and Date: 2016-01-19
  • Int'l Joint Research / Invited
• [Presentation] Experimental Approaches to Strangeness in Neutron Stars (2016)
  • Author(s): H. Tamura
  • Organizer: 14th International Symposium on Nuclei in the Cosmos (NIC14)
  • Int'l Joint Research / Invited
• [Presentation] Recent Progress in Hypernuclear Physics (2016)
  • Author(s): H. Tamura
  • Organizer: 25th International Nuclear Physics Conference (INPC2016)
  • Int'l Joint Research / Invited
• [Presentation] Strangeness nuclear physics and neutron stars (2016)
  • Author(s): H. Tamura
  • Organizer: Conference in the YIPQS long-term and Nishinomiya-Yukawa memorial workshop "Compact stars and gravitational waves"
  • Int'l Joint Research / Invited
• [Presentation] Hypernuclear Physics at J-PARC (2015)
  • Author(s): H. Tamura
  • Organizer: Frontiers in hadron and nuclear physics with strangeness and charm
  • Place of Presentation: ECT*, Trento, Italy
  • Year and Date: 2015-10-19
  • Int'l Joint Research
• [Presentation] Gamma-ray spectroscopy of Lambda hypernuclei at J-PARC (2015)
  • Author(s): T. Koike
  • Organizer: International symposium on the “Frontier of γ-ray spectroscopy” (Gamma15)
  • Place of Presentation: Osaka University, Toyonaka, Osaka, Japan
  • Year and Date: 2015-09-30
  • Int'l Joint Research / Invited
• [Presentation] Gamma-ray spectroscopy of 4ΛHe hypernuclei with Hyperball-J (2015)
  • Author(s): T.O. Yamamoto
  • Organizer: International symposium on the “Frontier of γ-ray spectroscopy” (Gamma15)
  • Place of Presentation: Osaka University, Toyonaka, Osaka, Japan
  • Year and Date: 2015-09-30
  • Int'l Joint Research / Invited
• [Presentation] (K-,π-)反応を用いた4ΛHeのガンマ線分光 (2015)
  • Author(s): 山本剛史 for the J-PARC E13 collaboration (田村裕和、小池武志ほか）
  • Organizer: 日本物理学会2015年秋季大会
  • Place of Presentation: 大阪市大、大阪市住吉区
  • Year and Date: 2015-09-25
• [Presentation] Gamma-ray spectroscopy of hypernuclei - recent results and prospects at J-PARC (2015)
  • Author(s): H. Tamura
  • Organizer: The 12th International Conference on Hypernuclear and Strange Particle Physics (HYP2015)
  • Place of Presentation: Tohoku University, Sendai, Japan
  • Year and Date: 2015-09-07
  • Int'l Joint Research / Invited
• [Presentation] Prospect of gamma-ray spectroscopy of 4ΛH at J-PARC (2015)
  • Author(s): M. Ukai
  • Organizer: The 12th International Conference on Hypernuclear and Strange Particle Physics (HYP2015)
  • Place of Presentation: Tohoku University, Sendai, Japan
  • Year and Date: 2015-09-07
  • Int'l Joint Research
• [Remarks] 重いハイパー核(フッ素19ラムダ核) の構造解明に成功－中性子星の内部構造を理解する手かがりに－」
  • URL: https://www2.kek.jp/ipns/ja/release/hyper/
• [Remarks] J-PARCハドロン実験施設で"奇妙な粒子" が原子核の荷電対称性を破る現象を発見
  • URL: http://www.kek.jp/ja/NewsRoom/Release/20151125150000/
• [Remarks] 原子核物理学の基本法則「荷電対称性」を大きく破る「奇妙な粒子」
  • URL: http://www.phys.tohoku.ac.jp/topics/topics-2010/
• [Remarks] 【プレスリリース】J-PARCハドロン実験施設で"奇妙な粒子"が原子核の荷電対称性を破る現象を発見
  • URL: http://www.sci.tohoku.ac.jp/news/20151125-3744.html
• [Remarks] 原子核物理学の基本法則「荷電対称性」を大きく破る「奇妙な粒子」 （東北大理物理 トピックス）
  • URL: http://www.phys.tohoku.ac.jp/topics/topics-2010/