Development of an active magnetic field compensation system for experimental searches of physics beyond the Standard Model

2023 Fiscal Year Final Research Report

• Project/Area Number: 19K23442
• Research Category: Grant-in-Aid for Research Activity Start-up
• Allocation Type: Multi-year Fund
• Review Section: 0203:Particle-, nuclear-, astro-physics, and related fields
• Research Institution: Osaka University
• Principal Investigator: Higuchi Takashi 大阪大学, 核物理研究センター, 招へい准教授 (90843772)
• Project Period (FY): 2019-08-30 – 2024-03-31
• Keywords: 電気双極子モーメント / CP対称性の破れ / 時間反転対称性 / 基本的対称性 / 磁場安定化 / 超冷中性子 / 中性子

Outline of Final Research Achievements

In this project, a dynamic magnetic-field compensation system for a neutron EDM experiment has been developed, as a part of the international TUCAN collaboration. First, magnetic field monitoring was performed at the TRIUMF Meson Hall, where the EDM experiment is going to be built. Based on this, we set the main target of the dynamic magnetic field compensation to be magnetic field variations produced by motions of the bridge crane of the facility and aimed to prolong the uptime of the EDM measurement during the daytime by compensating them. Next, using a 5.5 m x 5.5 m square coil, we performed a compensation test of crane-induced magnetic field variations, and demonstrated the compensation with a shielding factor of 6. Based on this, we designed rectangular coils surrounding the TCUAN magnetic shield, and built a prototype coil to test the parts and the construction procedures.

Free Research Field

素粒子物理学

Academic Significance and Societal Importance of the Research Achievements

本研究を通して、TRIUMFの中性子EDM実験のための動的磁場補償システムを開発した。製作前に行った試験によれば、これによって、実験施設内の主な磁場変動要因となる天井クレーン由来の磁場変動を約6分の1に抑制し、EDM測定が可能な時間帯を大幅に拡大することができる。本研究で得られた知見は、精密な磁場制御が要求される他の加速器施設での実験にも役立てることができる。