Study on Thorium-229 low-lying isomeric state

2017 Fiscal Year Final Research Report

• Project/Area Number: 15H03661
• 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: Okayama University
• Principal Investigator: Yoshimura Koji 岡山大学, 異分野基礎科学研究所, 教授 (50272464)
• Co-Investigator(Kenkyū-buntansha): 吉見 彰洋 岡山大学, 異分野基礎科学研究所, 准教授 (40333314) ; 笹尾 登 岡山大学, 異分野基礎科学研究所, 特任教授 (10115850)
• Co-Investigator(Renkei-kenkyūsha): YAMAGUCHI Atsushi 理化学研究所, 香取量子計測研究室, 研究員 (70724805) ; SETO Makoto 京都大学, 原子炉実験所, 教授 (40243109)
• Research Collaborator: Stellmer Simon ウィーン工科大学, 研究員
• Project Period (FY): 2015-04-01 – 2018-03-31
• Keywords: 原子核時計 / 核共鳴散乱 / X線検出器 / トリウム / APD / 周波数標準 / 物理定数の経年変化

Outline of Final Research Achievements

We searched for eV-order meta-stable isomeric excited state of Th-229, which is extraordinally low-lying for ordinary nuclei. We developed the new scheme using nuclear resonant scattering with high intense synchrotron radiation X-ray source, fast X-ray detection system, high performance targetry, and X-ray focusing system. We have successfully observed the precise signal from nuclear resonant scattering of nuclei with half life below 1 ns.

Free Research Field

素粒子実験