Precision measurement of nuclear reactions with polarized neutrons for time-reversal violation search

• Project/Area Number: 17H02889
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Particle/Nuclear/Cosmic ray/Astro physics
• Research Institution: Nagoya University
• Principal Investigator: Kitaguchi Masaaki 名古屋大学, 素粒子宇宙起源研究所, 准教授 (90397571)
• Co-Investigator(Kenkyū-buntansha): 吉岡 瑞樹 九州大学, 先端素粒子物理研究センター, 准教授 (20401317)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Project Status: Completed (Fiscal Year 2020)
• Budget Amount: ¥16,120,000 (Direct Cost: ¥12,400,000、Indirect Cost: ¥3,720,000); Fiscal Year 2019: ¥2,730,000 (Direct Cost: ¥2,100,000、Indirect Cost: ¥630,000); Fiscal Year 2018: ¥3,770,000 (Direct Cost: ¥2,900,000、Indirect Cost: ¥870,000); Fiscal Year 2017: ¥9,620,000 (Direct Cost: ¥7,400,000、Indirect Cost: ¥2,220,000)
• Keywords: 中性子 / 時間反転対称性の破れ / CP対称性の破れ / 偏極中性子 / 原子核反応 / J-PARC / 偏極 / 時間反転対称性 / CP対称性 / 複合核 / 原子核（実験） / 対称性の破れ / 素粒子物理実験 / 原子核物理実験 / 原子核(実験)

Outline of Final Research Achievements

A high performance neutron polarizer with 3He was developed and installed into the beamline BL04 ANNRI in J-PARC. The angular distribution of gamma rays from neutron capture reaction of 139La was clearly observed with the polarized epithermal neutrons. The distributions with polarized and unpolarized neutrons were analyzed with the theory for nuclear reactions. The results tells us that the large enhancement of time-reversal violation in nuclear reaction can be used for search for new physics beyond the standard model with the sensitivity as high as neutron electric dipole moment search.

Academic Significance and Societal Importance of the Research Achievements

宇宙の物質の起源を説明するための物質と反物質の性質の違いがCP対称性の破れであるが、現在の素粒子標準理論では十分に説明できていない。ある種の原子核反応では、基本的な素粒子反応における対称性の破れが増幅して観測される場合がある。本研究では偏極中性子ビームを用いて原子核反応を詳細に調べた。139La原子核の反応ではこの増幅が十分大きく、標準理論を超える物理法則の探索に利用できることがわかった。今回のデータは原子核反応を用いた時間反転対称性の破れの探索実験の基礎データとなる。

Research Products

• [Journal Article] Transverse asymmetry of γ rays from neutron-induced compound states of La140 (2020)
  • Author(s): Yamamoto T.、Okudaira T.、Endo S.、Fujioka H.、Hirota K.、Ino T.、Ishizaki K.、Kimura A.、Kitaguchi M.、Koga J.、Makise S.、Niinomi Y.、Oku T.、Sakai K.、Shima T.、Shimizu H. M.、Takada S.、Tani Y.、Yoshikawa H.、Yoshioka T.
  • Journal Title: Physical Review C Volume: 101 Issue: 6 Pages: 064624-064624
  • DOI: 10.1103/physrevc.101.064624
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Measurement of the angular distribution of γ-rays after neutron capture by 139La for a T-violation search (2019)
  • Author(s): Okudaira Takuya et al.
  • Journal Title: EPJ Web of Conferences Volume: 219 Pages: 09001-09001
  • DOI: 10.1051/epjconf/201921909001
  • Peer Reviewed / Open Access
• [Journal Article] Measurement of P-Violation in 139La(n,γ)140La ? a first step towards a T-Violation search (2019)
  • Author(s): Yamamoto Tomoki、Shimizu Hirohiko M.、Kitaguchi Masaaki、et. al.
  • Journal Title: EPJ Web of Conferences Volume: 219 Pages: 09002-09002
  • DOI: 10.1051/epjconf/201921909002
  • Peer Reviewed / Open Access
• [Journal Article] Measurement of the angular distribution of γ-rays emitted from the compound state after neutron capture by 81Br for a search of T-violation (2019)
  • Author(s): Endo Shunsuke、Shimizu Hirohiko M.、Kitaguchi Masaaki、Katsuya Hirota、Yamamoto Tomoki、Ishizaki Kohei、Sato Takumi、Yoshioka Tamaki、Takada Shusuke、Koga Jun、Okudaira Takuya、Sakai Kenji、Kimura Atsushi、Haddock Christopher C.
  • Journal Title: EPJ Web of Conferences Volume: 219 Pages: 09003-09003
  • DOI: 10.1051/epjconf/201921909003
  • Peer Reviewed / Open Access
• [Journal Article] Measurement of the angular distribution of prompt gamma-rays emitted in the 117Sn(n, γ) reaction for a T-violation search (2019)
  • Author(s): Koga Jun、Takada Shusuke、Yoshioka Tamaki、Shimizu Hirohiko M.、Hirota Katsuya、Oi Norio、Yamamoto Tomoki、Ito Ikuya、Ishizaki Kohei、Endo Shunsuke、Sato Takumi、Kitaguchi Masaaki、Haddock Christopher C.、Okudaira Takuya、Sakai Kenji、Kimura Atsushi
  • Journal Title: EPJ Web of Conferences Volume: 219 Pages: 09004-09004
  • DOI: 10.1051/epjconf/201921909004
  • Peer Reviewed / Open Access
• [Journal Article] Development of a Neutron Spin Filter for a T Violation Search in Compound Nuclei (2018)
  • Author(s): Yamamoto T.、Shimizu H. M.、Kitaguchi M.、Hirota K.、Okudaira T.、Haddock C. C.、Oi N.、Ito I.、Endo S.、Takada S.、Koga J.、Yoshioka T.、Ino T.、Asahi K.、Momose T.、Iwata T.、Sakai K.、Oku T.、Kimura A.、Hino M.、Shima T.、Yamagata Y.
  • Journal Title: Proceedings of the International Conference on Neutron Optics (NOP2017) Volume: 22 Pages: 011018-011018
  • DOI: 10.7566/jpscp.22.011018
  • Peer Reviewed / Open Access
• [Journal Article] Development of High-Counting-Rate Neutron Detector for CP-Violation Search in Neutron-Induced Reactions (2018)
  • Author(s): Endo Shunsuke、Shimizu Hirohiko M.、Kitaguchi Masaaki、Hirota Katsuya、Satoh Setsuo、Kai Tetsuya、Okudaira Takuya、Haddock Christopher C.、Oi Noriko、Goto Fumiya、Ito Ikuya、Nakaji Masaya、Takada Shusuke、Koga Jun、Yoshioka Tamaki、Sakai Kenji
  • Journal Title: Proceedings of the International Conference on Neutron Optics (NOP2017) Volume: 22 Pages: 011021-011021
  • DOI: 10.7566/jpscp.22.011021
  • Peer Reviewed / Open Access
• [Journal Article] Fundamental Physics Using High-Performance Optics (2018)
  • Author(s): Kitaguchi Masaaki,Asahi Koichiro,Endo Shunsuke,Haddock Christopher C.,Hino Masahiro,Hirota Katsuya,Ino Takashi,Ito Ikuya,Iwata Takahiro,Koga Jun,Miyachi Yoshiyuki,Momose Takamasa,Oi Noriko,Okudaira Takuya,Sakai Kenji,Shima Tatsushi,Shimizu Hirohiko M.,Takada Shusuke,Yamagata Yutaka,Yamamoto Tomoki,Yoshioka Tamaki
  • Journal Title: Proceedings of the International Conference on Neutron Optics (NOP2017) Volume: 22 Pages: 011034-011034
  • DOI: 10.7566/jpscp.22.011034
  • Peer Reviewed / Open Access
• [Journal Article] Measurement of (n,gamma) Reaction of 117Sn for T-Violation Search by Using Compound Nucleus (2018)
  • Author(s): Koga J.、Takada S.、Yoshioka T.、Shimizu H. M.、Hirota K.、Okudaira T.、Oi N.、Ito I.、Yamamoto T.、Endo S.、Haddock C. C.、Kitaguchi M.、Kimura A.、Sakai K.、Ino T.、Asahi K.、Momose T.、Iwata T.、Hino M.、Shima T.、Yamagata Y.
  • Journal Title: Proceedings of the International Conference on Neutron Optics (NOP2017) Volume: 22 Pages: 011035-011035
  • DOI: 10.7566/jpscp.22.011035
  • Peer Reviewed / Open Access
• [Journal Article] Measurement of Angular Distributions in 139La(n,gamma) Reaction for T Violation Search (2018)
  • Author(s): Okudaira T.、Shimizu H. M.、Kitaguchi M.、Hirota K.、Haddock C. C.、Oi N.、Ito I.、Yamamoto T.、Endo S.、Takada S.、Koga J.、Yoshioka T.、Ino T.、Asahi K.、Momose T.、Iwata T.、Sakai K.、Oku T.、Kimura A.、Hino M.、Shima T.、Yamagata Y.
  • Journal Title: Proceedings of the International Conference on Neutron Optics (NOP2017) Volume: 22 Pages: 011041-011041
  • DOI: 10.7566/jpscp.22.011041
  • Peer Reviewed / Open Access
• [Journal Article] Angular distribution of γ rays from neutron-induced compound states of La140 (2018)
  • Author(s): Okudaira T.、Takada S.、Hirota K.、Kimura A.、Kitaguchi M.、Koga J.、Nagamoto K.、Nakao T.、Okada A.、Sakai K.、Shimizu H. M.、Yamamoto T.、Yoshioka T.
  • Journal Title: Physical Review C Volume: 97 Issue: 3 Pages: 034622-034622
  • DOI: 10.1103/physrevc.97.034622
  • Peer Reviewed
• [Journal Article] Characterization of germanium detectors for the measurement of the angular distribution of prompt γ-rays at the ANNRI in the MLF of the J-PARC (2018)
  • Author(s): Takada S.、Okudaira T.、Goto F.、Hirota K.、Kimura A.、Kitaguchi M.、Koga J.、Nakao T.、Sakai K.、Shimizu H.M.、Yamamoto T.、Yoshioka T.
  • Journal Title: Journal of Instrumentation Volume: 13 Issue: 02 Pages: P02018-P02018
  • DOI: 10.1088/1748-0221/13/02/p02018
  • Peer Reviewed
• [Journal Article] Search for unknown interaction with neutrons (2017)
  • Author(s): Kitaguchi Masaaki
  • Journal Title: Proceedings of Science Volume: KMI2017 Pages: 8-8
  • DOI: 10.22323/1.294.0008
• [Journal Article] Measurement of angular correlation of (n,gamma) reaction with polarized neutrons (2017)
  • Author(s): Yamamoto Tomoki、M.Shimizu H、Kitaguchi M.、Hirota K.、Okudaira T.、Takada S.、Okada A.、Yoshioka T.、Ino T.、Sakai K.、Asahi K.、Momose T.、Iwata T.、Hino M.、Shima T.、Yamagata Y.
  • Journal Title: Proceedings of Science Volume: KMI2017 Pages: 49-49
  • DOI: 10.22323/1.294.0049
• [Presentation] 複合核共鳴における時間反転対称性の破れ探索に向けた偏極中性子による139La(n,γ)反応の解析 (2020)
  • Author(s): 山本知樹
  • Organizer: 日本物理学会2020年秋季大会
• [Presentation] 複合核過程における時間反転対称性の破れ探索にむけた偏極中性子を用いた139La(n,γ)反応の研究 (2019)
  • Author(s): 山本知樹
  • Organizer: 日本物理学会 第74回年次大会
• [Presentation] Verification of the compound nuclear model for T-violation search (2019)
  • Author(s): T.Yamamoto, H.M.Shimizu, M.Kitaguchi, K.Hirota, S.Takada (for NOPTREX collaborator)
  • Organizer: KMI2019
  • Int'l Joint Research
• [Presentation] Neutron Experiments at J-PARC (2019)
  • Author(s): M. Kitaguchi
  • Organizer: KMI2019
  • Int'l Joint Research
• [Presentation] 量子論的増幅効果と新物理探索 (2019)
  • Author(s): 北口雅暁
  • Organizer: 日本物理学会第74回年次大会
• [Presentation] Optical behavior from epithermal to ultra-cold neutrons (2018)
  • Author(s): M. Kitaguchi
  • Organizer: PPNS2018
  • Int'l Joint Research
• [Presentation] Discrete symmetry in compound nuclei (2018)
  • Author(s): M. Kitaguchi
  • Organizer: 5th Joint Meeting of the Nuclear Physics Divisions of APS and JPS (HAW2018)
  • Int'l Joint Research / Invited
• [Presentation] Measurement of angular distribution of γ-rays in the resonance reaction of 139La for T-Violation search experiment (2018)
  • Author(s): M. Kitaguchi
  • Organizer: 5th Joint Meeting of the Nuclear Physics Divisions of APS and JPS (HAW2018)
  • Int'l Joint Research
• [Presentation] Search for T-violation efects in compound neutron resonance at J-PARC (2018)
  • Author(s): Masaaki Kitaguchi
  • Organizer: 10th International Workshop on Fundamental Physics using Atoms
  • Int'l Joint Research
• [Presentation] Fundamental physics using high-performance optics (2017)
  • Author(s): Masaaki Kitaguchi
  • Organizer: International Conference on Neutron Optics 2017
  • Int'l Joint Research
• [Presentation] 複合核状態における時間反転対称性の破れ 探索実験計画 (2017)
  • Author(s): 北口雅暁
  • Organizer: 日本物理学会 2017 年秋季大会
• [Presentation] 複合核状態における時間反転対称性の破れ探索のための偏極中性子を用いた空間反転対称性の破れ測定 (2017)
  • Author(s): 山本知樹
  • Organizer: 日本物理学会 2017 年秋季大会