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Yamaguchi Atsushi  山口 敦史

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YAMAGUCHI Atsushi  山口 敦史

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Researcher Number 70724805
Other IDs
Affiliation (Current) 2025: 国立研究開発法人理化学研究所, 光量子工学研究センター, 専任研究員
Affiliation (based on the past Project Information) *help 2021 – 2024: 国立研究開発法人理化学研究所, 開拓研究本部, 専任研究員
2018 – 2020: 国立研究開発法人理化学研究所, 開拓研究本部, 研究員
2017: 理化学研究所, 香取量子計測研究室, 研究員
Review Section/Research Field
Principal Investigator
Medium-sized Section 13:Condensed matter physics and related fields / Basic Section 15020:Experimental studies related to particle-, nuclear-, cosmic ray and astro-physics
Except Principal Investigator
Medium-sized Section 15:Particle-, nuclear-, astro-physics, and related fields / Basic Section 15020:Experimental studies related to particle-, nuclear-, cosmic ray and astro-physics / Particle/Nuclear/Cosmic ray/Astro physics
Keywords
Principal Investigator
原子核時計 / カロリーメーター / 原子核分光 / 原子時計 / 超伝導転移端センサー / ガンマ線分光
Except Principal Investigator
原子核時計 / 核共鳴散乱 / イオントラップ / 核異性体 … More / トリウム229 / トリウム / 真空紫外光 / レーザ-による原子核操作 / 物理定位数の時間変化 / 物理定数の時間変化 / 真空紫外レーザー分光 / レーザーによる原子核操作 / レーザー励起 / 能動的核異性体生成 / 高時間分解能X線測定 / アイソマー / 放射光 / 高時間分解能 / 放射光X線 / 実験核物理 / 物理定数の経年変化 / 周波数標準 / APD / X線検出器 Less
  • Research Projects

    (6 results)
  • Research Products

    (45 results)
  • Co-Researchers

    (15 People)
  •  原子核時計実現にむけたトリウム229イオンのレーザー冷却Principal Investigator

    • Principal Investigator
      山口 敦史
    • Project Period (FY)
      2023 – 2025
    • Research Category
      Grant-in-Aid for Scientific Research (A)
    • Review Section
      Medium-sized Section 13:Condensed matter physics and related fields
    • Research Institution
      Institute of Physical and Chemical Research
  •  トリウム229核異性体の内部転換抑制手法の開発によるガンマ線放出過程の解明

    • Principal Investigator
      重河 優大
    • Project Period (FY)
      2023 – 2026
    • Research Category
      Grant-in-Aid for Scientific Research (B)
    • Review Section
      Basic Section 15020:Experimental studies related to particle-, nuclear-, cosmic ray and astro-physics
    • Research Institution
      Institute of Physical and Chemical Research
  •  レーザーによるコヒーレントな原子核操作の実現ー原子核時計の創成と応用に向けて

    • Principal Investigator
      吉村 浩司
    • Project Period (FY)
      2021 – 2024
    • Research Category
      Grant-in-Aid for Scientific Research (A)
    • Review Section
      Medium-sized Section 15:Particle-, nuclear-, astro-physics, and related fields
    • Research Institution
      Okayama University
  •  Precision laser spectroscopy of thorium-229 nuclear isomers approached by active isomer pumping method

    • Principal Investigator
      Masuda Takahiko
    • Project Period (FY)
      2019 – 2022
    • Research Category
      Grant-in-Aid for Scientific Research (A)
    • Review Section
      Medium-sized Section 15:Particle-, nuclear-, astro-physics, and related fields
    • Research Institution
      Okayama University
  •  Energy measurement of the Thorium-229 nuclear isomer toward a nuclear clockPrincipal Investigator

    • Principal Investigator
      Yamaguchi Atsushi
    • Project Period (FY)
      2018 – 2022
    • Research Category
      Grant-in-Aid for Scientific Research (B)
    • Review Section
      Basic Section 15020:Experimental studies related to particle-, nuclear-, cosmic ray and astro-physics
    • Research Institution
      Institute of Physical and Chemical Research
  •  Study on Thorium-229 low-lying isomeric state

    • Principal Investigator
      Yoshimura Koji
    • Project Period (FY)
      2015 – 2017
    • Research Category
      Grant-in-Aid for Scientific Research (B)
    • Research Field
      Particle/Nuclear/Cosmic ray/Astro physics
    • Research Institution
      Okayama University

All 2024 2023 2022 2021 2020 2019 2018 2017 Other

All Journal Article Presentation Other

  • [Journal Article] Laser spectroscopy of triply charged 229Th isomer for a nuclear clock2024

    • Author(s)
      Yamaguchi Atsushi、Shigekawa Yudai、Haba Hiromitsu、Kikunaga Hidetoshi、Shirasaki Kenji、Wada Michiharu、Katori Hidetoshi
    • Journal Title

      Nature

      Volume: 629 Issue: 8010 Pages: 62-66

    • DOI

      10.1038/s41586-024-07296-1

    • Peer Reviewed / Int'l Joint Research
    • Data Source
      KAKENHI-PROJECT-21H04473, KAKENHI-PROJECT-23K25904
  • [Journal Article] Extraction of 229Th3+,2+ using RF carpet gas cell and observation of internal conversion process of 229mTh2023

    • Author(s)
      Y. Shigekawa, A. Yamaguchi, K. Tokoi, N. Sato, M. Wada, H. Haba
    • Journal Title

      RIKEN Accel. Prog. Rep.

      Volume: 56

    • Peer Reviewed
    • Data Source
      KAKENHI-PROJECT-23K25904
  • [Journal Article] 最小エネルギーをもつトリウム 229 アイソマー状態の人工的生成―原子核時計の実現に向けて2021

    • Author(s)
      増田孝彦、吉見彰洋、山口敦史、吉村浩司
    • Journal Title

      日本物理学会誌

      Volume: 76 Pages: 456-456

    • NAID

      130008062444

    • Data Source
      KAKENHI-PROJECT-19H00685
  • [Journal Article] Absolute X-ray energy measurement using a high-accuracy angle encoder2021

    • Author(s)
      Masuda Takahiko、Watanabe Tsukasa、Beeks Kjeld、Fujimoto Hiroyuki、Hiraki Takahiro、Kaino Hiroyuki、Kitao Shinji、Miyamoto Yuki、Okai Koichi、Sasao Noboru、Seto Makoto、Schumm Thorsten、Shigekawa Yudai、Tamasaku Kenji、Uetake Satoshi、Yamaguchi Atsushi、Yoda Yoshitaka、Yoshimi Akihiro、Yoshimura Koji
    • Journal Title

      Journal of Synchrotron Radiation

      Volume: 28 Issue: 1 Pages: 111-119

    • DOI

      10.1107/s1600577520014526

    • NAID

      120006956810

    • Peer Reviewed / Open Access / Int'l Joint Research
    • Data Source
      KAKENHI-PROJECT-20K14500, KAKENHI-PROJECT-19H00685, KAKENHI-PROJECT-18H01230, KAKENHI-PROJECT-18J22641, KAKENHI-PROJECT-19K21879, KAKENHI-PROJECT-19K14740, KAKENHI-PROJECT-19K23445
  • [Journal Article] Estimation of radiative half-life of 229mTh by half-life measurement of other nuclear excited states in 229Th2021

    • Author(s)
      Shigekawa Y.、Yamaguchi A.、Suzuki K.、Haba H.、Hiraki T.、Kikunaga H.、Masuda T.、Nishimura S.、Sasao N.、Yoshimi A.、Yoshimura K.
    • Journal Title

      Physical Review C

      Volume: 104 Issue: 2 Pages: 024306-024306

    • DOI

      10.1103/physrevc.104.024306

    • Peer Reviewed
    • Data Source
      KAKENHI-PROJECT-18K18759, KAKENHI-PROJECT-19H00685, KAKENHI-PROJECT-18H01241, KAKENHI-PROJECT-20K14500
  • [Journal Article] 最小エネルギーをもつトリウム 229 アイソマー状態の人工的生成―原子核時計の実現に向けて2021

    • Author(s)
      増田孝彦、吉見彰洋、山口敦史、吉村浩司
    • Journal Title

      日本物理学会誌

      Volume: 76 Pages: 456-456

    • NAID

      130008062444

    • Data Source
      KAKENHI-PROJECT-21H04473
  • [Journal Article] Nuclear resonant scattering experiment with fast time response: Photonuclear excitation of 201Hg2018

    • Author(s)
      A. Yoshimi et al.
    • Journal Title

      Physical Review C

      Volume: 97 Issue: 2 Pages: 024607-024607

    • DOI

      10.1103/physrevc.97.024607

    • Peer Reviewed / Int'l Joint Research
    • Data Source
      KAKENHI-PROJECT-17K14291, KAKENHI-PROJECT-15H03661, KAKENHI-PROJECT-16H04172, KAKENHI-PROJECT-16J06700
  • [Journal Article] Fast x-ray detector system with simultaneous measurement of timing and energy for a single photon2017

    • Author(s)
      Masuda T.、Okubo S.、Hara H.、Hiraki T.、Kitao S.、Miyamoto Y.、Okai K.、Ozaki R.、Sasao N.、Seto M.、Uetake S.、Yamaguchi A.、Yoda Y.、Yoshimi A.、Yoshimura K.
    • Journal Title

      Review of Scientific Instruments

      Volume: 88 Issue: 6 Pages: 063105-063105

    • DOI

      10.1063/1.4989405

    • Peer Reviewed
    • Data Source
      KAKENHI-PROJECT-17K14291, KAKENHI-PROJECT-15H03661, KAKENHI-PROJECT-16H04172, KAKENHI-PROJECT-17H02896
  • [Presentation] 原子核時計実現にむけたトリウムイオンのレーザー分光2023

    • Author(s)
      山口敦史, 重河優大, 羽場宏光, 和田道治, 香取秀俊
    • Organizer
      電子回路研究会 次世代周波数精密計測の基礎と応用
    • Data Source
      KAKENHI-PROJECT-23H00094
  • [Presentation] Th-229mイオンの引き出しとイオントラップ実験の現状2023

    • Author(s)
      重河優大, 山口敦史, 床井健運, 佐藤望, 笠松良崇, 和田道治, 羽場宏光
    • Organizer
      日本放射化学会第67回討論会(2023)
    • Data Source
      KAKENHI-PROJECT-23K25904
  • [Presentation] Extraction and trapping of 229mTh ions for measuring nuclear-decay half-lives of various ionic species of 229mTh and observing electronic bridge process2023

    • Author(s)
      Yudai Shigekawa, Atsushi Yamaguchi, Katsuyuki Tokoi, Nozomi Sato, Michiharu Wada, Hiromitsu Haba
    • Organizer
      6th Joint Meeting of the APS Division of Nuclear Physics and the Physical Society of Japan (HAWAII2023)
    • Int'l Joint Research
    • Data Source
      KAKENHI-PROJECT-23K25904
  • [Presentation] Laser spectroscopy of triply charged Th-229 toward a nuclear clock2023

    • Author(s)
      Atsushi Yamaguchi
    • Organizer
      Quantum Innovation 2023
    • Invited / Int'l Joint Research
    • Data Source
      KAKENHI-PROJECT-23H00094
  • [Presentation] 原子核時計実現にむけたトリウムイオンのレーザー分光2023

    • Author(s)
      山口敦史, 重河優大, 羽場宏光, 菊永英寿, 白崎謙次, 和田道治, 香取秀俊
    • Organizer
      日本放射化学会第67回討論会(2023)
    • Invited
    • Data Source
      KAKENHI-PROJECT-23K25904
  • [Presentation] 原子核時計実現にむけたトリウムイオンのトラップとレーザー分光2023

    • Author(s)
      山口敦史, 重河優大, 羽場宏光, 和田道治, 香取秀俊
    • Organizer
      レーザー学会学術講演会 第43会年次大会
    • Invited
    • Data Source
      KAKENHI-PROJECT-19H00685
  • [Presentation] Laser Spectroscopy of Triply Charged Thorium Ions Towards a Nuclear Clock2023

    • Author(s)
      A. Yamaguchi, Y. Shigekawa, H. Haba, M. Wada, H. Katori
    • Organizer
      IEEE IFCS-EFTF2023
    • Int'l Joint Research
    • Data Source
      KAKENHI-PROJECT-23H00094
  • [Presentation] Laser Spectroscopy of Triply Charged Thorium-229 Isomer Toward a Nuclear Clock2023

    • Author(s)
      A. Yamaguchi, Y. Shigekawa, H. Haba, M. Wada, H. Katori
    • Organizer
      The 9th Symposium on Frequency Standards and Metrology
    • Int'l Joint Research
    • Data Source
      KAKENHI-PROJECT-23K25904
  • [Presentation] 原子核時計実現にむけたトリウムイオンのレーザー分光2023

    • Author(s)
      山口敦史, 重河優大, 羽場宏光, 菊永英寿, 白崎謙次, 和田道治, 香取秀俊
    • Organizer
      日本放射化学会第67回討論会
    • Invited
    • Data Source
      KAKENHI-PROJECT-23H00094
  • [Presentation] Trapping and laser spectroscopy of triply charged thorium ions towards a nuclear clock2023

    • Author(s)
      A. Yamaguchi, Y. Shigekawa, H. Haba, M. Wada, and H. Katori
    • Organizer
      International Conference on Stopping and Manipulation of Ions and Related Topics (SMI-2023)
    • Invited / Int'l Joint Research
    • Data Source
      KAKENHI-PROJECT-23K25904
  • [Presentation] Laser Spectroscopy of Triply Charged Thorium Ions Towards a Nuclear Clock2023

    • Author(s)
      A. Yamaguchi, Y. Shigekawa, H. Haba, H. Katori, M. Wada
    • Organizer
      Joint Conference of the IEEE International Frequency Control Symposium and the European Frequency and Time Forum (IEEE IFCS-EFTF 2023)
    • Int'l Joint Research
    • Data Source
      KAKENHI-PROJECT-23K25904
  • [Presentation] Development of a cryogenic RF-carpet gas cell for the chemistry of superheavy elements2023

    • Author(s)
      Y. Shigekawa, A. Yamaguchi, N. Sato, A. Takamine, M. Wada, H. Haba
    • Organizer
      7th International Conference on the Chemistry and Physics of the Transactinide Elements (TAN 23)
    • Int'l Joint Research
    • Data Source
      KAKENHI-PROJECT-23K25904
  • [Presentation] 原子核時計実現にむけたトリウムイオンのトラップとレーザー分光2023

    • Author(s)
      山口敦史, 重河優大, 羽場宏光, 和田道治, 香取秀俊
    • Organizer
      レーザー学会学術講演会 第43会年次大会
    • Invited
    • Data Source
      KAKENHI-PROJECT-18H01241
  • [Presentation] Laser Spectroscopy of Triply Charged Thorium Ions Towards a Nuclear Clock2023

    • Author(s)
      A. Yamaguchi, Y. Shigekawa, H. Haba, M. Wada, H. Katori
    • Organizer
      14th International Conference on Stopping and Manipulation of Ions and Related Topics
    • Invited / Int'l Joint Research
    • Data Source
      KAKENHI-PROJECT-23H00094
  • [Presentation] Laser Spectroscopy of Triply Charged Thorium-229 Isomer Toward a Nuclear Clock2023

    • Author(s)
      A. Yamaguchi, Y. Shigekawa, H. Haba, M. Wada, H. Katori
    • Organizer
      The 9th Symposium on Frequency Standards and Metrology
    • Invited / Int'l Joint Research
    • Data Source
      KAKENHI-PROJECT-23H00094
  • [Presentation] Laser spectroscopy of triply charged thorium ions towards a nuclear clock2022

    • Author(s)
      A. Yamaguchi, Y. Shigekawa, H. Haba, M. Wada, and H. Katori
    • Organizer
      2022 URSI-Japan Radio Science Meeting
    • Invited / Int'l Joint Research
    • Data Source
      KAKENHI-PROJECT-18H01241
  • [Presentation] An optical nuclear clock2022

    • Author(s)
      A. Yamaguchi
    • Organizer
      Virtual Humboldt Colloquium, “Top Global Research” and the Humboldt network: New Frontiers of German-Japanese Scientific Cooperation
    • Int'l Joint Research
    • Data Source
      KAKENHI-PROJECT-18H01241
  • [Presentation] Laser spectroscopy of triply charged thorium ions towards a nuclear clock2022

    • Author(s)
      A. Yamaguchi, Y. Shigekawa, H. Haba, M. Wada, and H. Katori
    • Organizer
      2022 URSI-Japan Radio Science Meeting
    • Invited / Int'l Joint Research
    • Data Source
      KAKENHI-PROJECT-19H00685
  • [Presentation] 原子核時計実現にむけたトリウムイオントラップ装置の開発2022

    • Author(s)
      山口敦史, 重河優大, 羽場宏光, 和田道治, 香取秀俊
    • Organizer
      日本物理学会 2022年秋季大会
    • Data Source
      KAKENHI-PROJECT-18H01241
  • [Presentation] An optical nuclear clock2022

    • Author(s)
      A. Yamaguchi
    • Organizer
      Virtual Humboldt Colloquium, “Top Global Research” and the Humboldt network: New Frontiers of German-Japanese Scientific Cooperation
    • Int'l Joint Research
    • Data Source
      KAKENHI-PROJECT-19H00685
  • [Presentation] 原子核時計実現にむけたトリウムイオントラップ装置の開発2022

    • Author(s)
      山口敦史, 重河優大, 羽場宏光, 和田道治, 香取秀俊
    • Organizer
      日本物理学会 2022年秋季大会
    • Data Source
      KAKENHI-PROJECT-19H00685
  • [Presentation] Development of an RF-carpet gas cell to obtain an ion beam of thorium-2292021

    • Author(s)
      A. Yamaguchi, Y. Shigekawa, H. Haba, M. Wada, and H. Katori
    • Organizer
      ViCPEAC2021
    • Invited / Int'l Joint Research
    • Data Source
      KAKENHI-PROJECT-19H00685
  • [Presentation] Challenge to improve the 229Th isomer energy measurement with TES calorimeters2021

    • Author(s)
      K. Tanaka, K. Hirano, A. Yamaguchi, H. Muramatsu, T. Hayashi, N. Yuasa, K. Nakamura, M. Takimoto, H. Haba, K. Shirasaki, H. Kikunaga, K. Maehata, N. Y. Yamasaki, K. Mitsuda
    • Organizer
      19th International Workshop on Low Temperature Detectors
    • Int'l Joint Research
    • Data Source
      KAKENHI-PROJECT-18H01241
  • [Presentation] Development of an RF-carpet gas cell to obtain a low-energy thorium ion beam2021

    • Author(s)
      A. Yamaguchi, Y. Shigekawa, H. Haba, M. Wada, and H. Katori
    • Organizer
      Second Workshop of the Center for Time, Constants and Fundamental Symmetries (TCFS)
    • Int'l Joint Research
    • Data Source
      KAKENHI-PROJECT-19H00685
  • [Presentation] 原子核時計実現にむけたトリウム229イオントラップ装置の開発2021

    • Author(s)
      山口敦史
    • Organizer
      第17回 原子・分子・光科学(AMO)討論会
    • Data Source
      KAKENHI-PROJECT-19H00685
  • [Presentation] 原子核時計実現に向けたトリウム229アイソマーエネルギーの測定2020

    • Author(s)
      山口 敦史
    • Organizer
      2020年電子回路研究会 周波数精密計測とその応用
    • Data Source
      KAKENHI-PROJECT-18H01241
  • [Presentation] Energy of the Th-229 nuclear clock isomer determined by absolute gamma-ray energy difference2020

    • Author(s)
      Atsushi Yamaguchi
    • Organizer
      GIMRT-REMAS2020
    • Int'l Joint Research
    • Data Source
      KAKENHI-PROJECT-18H01241
  • [Presentation] Nuclear Clock based on Thorium-2292020

    • Author(s)
      山口 敦史
    • Organizer
      2020年度 東北大学金属材料研究所放射線業務従事者再教育
    • Data Source
      KAKENHI-PROJECT-18H01241
  • [Presentation] 原子核時計実現に向けたTh-229原子核時計遷移探索実験2019

    • Author(s)
      山口 敦史, 村松 はるか, 満田 和久, 湯浅 直樹, 前畑 京介, 中村 圭佑, 滝本 美咲, 羽場 宏光, 菊永 英寿
    • Organizer
      2019重元素核化学ワークショップ
    • Data Source
      KAKENHI-PROJECT-18H01241
  • [Presentation] 全固体型原子核時計実現に向けたトリウム229アイソマー状態のエネルギー測定2019

    • Author(s)
      山口 敦史
    • Organizer
      SMART2019
    • Invited
    • Data Source
      KAKENHI-PROJECT-18H01241
  • [Presentation] 超伝導遷移端カロリメータによるトリウム 229 アイソマーエネルギーの測定2019

    • Author(s)
      山口 敦史, 村松 はるか, 林 佑, 満田 和久, 湯浅 直樹, 前畑 京介, 中村 圭佑, 滝本 美咲, 菊永 英寿
    • Organizer
      日本物理学会 2019年秋季大会
    • Data Source
      KAKENHI-PROJECT-18H01241
  • [Presentation] Search for the low-energy nuclear transition in Th-229 towards a nuclear clock2019

    • Author(s)
      山口 敦史
    • Organizer
      アトムの会
    • Data Source
      KAKENHI-PROJECT-18H01241
  • [Presentation] トリウム229異性体のX線マイクロカロリメータを用いた分光実験2018

    • Author(s)
      村松 はるか, 湯浅 直樹, 林 佑, 紺野 良平, 山口 敦史, 満田 和久, 山崎 典子, 菊永 英寿, 中村 圭佑, 滝本 美咲, 前畑 京介
    • Organizer
      日本物理学会 第74回年次大会
    • Data Source
      KAKENHI-PROJECT-18H01241
  • [Presentation] TES型マイクロカロリーメータによる233U線源のγ線スペクトルの解析手法2018

    • Author(s)
      湯浅 直樹, 前畑 京介, 村松 はるか, 満田 和久, 山口 敦史, 中村 圭佑
    • Organizer
      第79回 応用物理学会秋季学術講演会
    • Data Source
      KAKENHI-PROJECT-18H01241
  • [Presentation] 原子核時計の実現に向けて2018

    • Author(s)
      山口 敦史
    • Organizer
      異分野基礎科学研究所特別講演会
    • Invited
    • Data Source
      KAKENHI-PROJECT-18H01241
  • []

  • []

  • 1.  重河 優大 (60845626)
    # of Collaborated Projects: 3 results
    # of Collaborated Products: 15 results
  • 2.  Yoshimura Koji (50272464)
    # of Collaborated Projects: 2 results
    # of Collaborated Products: 1 results
  • 3.  菊永 英寿 (00435645)
    # of Collaborated Projects: 2 results
    # of Collaborated Products: 6 results
  • 4.  北尾 真司 (00314295)
    # of Collaborated Projects: 2 results
    # of Collaborated Products: 0 results
  • 5.  SETO Makoto (40243109)
    # of Collaborated Projects: 1 results
    # of Collaborated Products: 0 results
  • 6.  Masuda Takahiko (90733543)
    # of Collaborated Projects: 1 results
    # of Collaborated Products: 1 results
  • 7.  吉見 彰洋 (40333314)
    # of Collaborated Projects: 1 results
    # of Collaborated Products: 0 results
  • 8.  笹尾 登 (10115850)
    # of Collaborated Projects: 1 results
    # of Collaborated Products: 0 results
  • 9.  満田 和久 (80183961)
    # of Collaborated Projects: 1 results
    # of Collaborated Products: 5 results
  • 10.  前畑 京介 (30190317)
    # of Collaborated Projects: 1 results
    # of Collaborated Products: 5 results
  • 11.  滝本 美咲 (40832316)
    # of Collaborated Projects: 1 results
    # of Collaborated Products: 4 results
  • 12.  中村 圭佑 (80705054)
    # of Collaborated Projects: 1 results
    # of Collaborated Products: 5 results
  • 13.  笠松 良崇 (70435593)
    # of Collaborated Projects: 1 results
    # of Collaborated Products: 0 results
  • 14.  Stellmer Simon
    # of Collaborated Projects: 1 results
    # of Collaborated Products: 0 results
  • 15.  平木 貴宏
    # of Collaborated Projects: 0 results
    # of Collaborated Products: 1 results

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