Development of a gravimeter based on magnetic levitation with diamagnets

• Project/Area Number: 26610139
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Solid earth and planetary physics
• Research Institution: The University of Tokyo
• Principal Investigator: Imanishi Yuichi 東京大学, 地震研究所, 准教授 (30260516)
• Co-Investigator(Kenkyū-buntansha): 高森 昭光 東京大学, 地震研究所, 助教 (00372425)
• Project Period (FY): 2014-04-01 – 2018-03-31
• Project Status: Completed (Fiscal Year 2017)
• Budget Amount: ¥3,120,000 (Direct Cost: ¥2,400,000、Indirect Cost: ¥720,000); Fiscal Year 2016: ¥910,000 (Direct Cost: ¥700,000、Indirect Cost: ¥210,000); Fiscal Year 2015: ¥1,430,000 (Direct Cost: ¥1,100,000、Indirect Cost: ¥330,000); Fiscal Year 2014: ¥780,000 (Direct Cost: ¥600,000、Indirect Cost: ¥180,000)
• Keywords: 磁気浮上 / 重力計

Outline of Final Research Achievements

In order to overcome the difficulties in gravimeters based on mechanical spring suspension, possibilities of a gravimeter based on magnetic suspension using diamagnets are investigated. A finite element method analysis on the system consisting of Neodimium magnets and pyrolytic carbon was conducted for its mechanical and electromagnetic properties. As a result, it was found that this system can be a good candidate as the basic principle of gravity sensors using magnetic suspension. The superconducting gravimeter, as one of the realizations of magnetic-suspension-type gravimeters, was also studied for its response to horizontal acceleration. It was shown that the mechanical eigenfrequency of the superconducting gravimeter CT-36 in the horizontal direction is approximately 3 Hz.

Research Products

• [Journal Article] Effects of horizontal acceleration on the superconducting gravimeter CT #036 at Ishigakijima, Japan (2018)
  • Author(s): Imanishi Yuichi、Nawa Kazunari、Tamura Yoshiaki、Ikeda Hiroshi
  • Journal Title: Earth, Planets and Space Volume: 70 Issue: 1
  • DOI: 10.1186/s40623-018-0777-9
  • NAID: 120007133818
  • Peer Reviewed / Open Access
• [Journal Article] Characterization of the room temperature payload prototype for the cryogenic interferometric gravitational wave detector KAGRA (2016)
  • Author(s): P. Arellano, F. Erasmo, T. Sekiguchi, Y. Fujii, R. Takahashi, M. Barton, N. Hirata, A. Shoda, J. van Heijningen, R. Flaminio, R. DeSalvo, K. Okutumi, T. Akutsu, Y. Aso, H. Ishizaki, N. Ohishi, K. Yamamoto, T. Uchiyama, O. Miyakawa, M. Kamiizumi, A. Takamori, et al.
  • Journal Title: Rev. Sci. Instrum. Volume: 87 Issue: 3 Pages: 034501-034501
  • DOI: 10.1063/1.4942909
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Presentation] 石垣島における超伝導重力計観測に及ぼす地下水の影響 (2016)
  • Author(s): 今西祐一，名和一成，田村良明，池田博，宮地竹史
  • Organizer: 日本地球惑星科学連合2016年大会
  • Place of Presentation: 幕張メッセ国際会議場（千葉県千葉市）
• [Presentation] 松代における超伝導重力計iGrav #028とTT70 #011の並行観測 (2016)
  • Author(s): 今西祐一，池田博
  • Organizer: 日本測地学会講演会
  • Place of Presentation: 奥州市文化会館（岩手県奥州市）
• [Presentation] 神岡における絶対重力測定と長期的重力変化 (2015)
  • Author(s): 今西祐一，名和一成，杉原光彦，宮川歩夢，田村良明，池田博
  • Organizer: 日本測地学会講演会
  • Place of Presentation: 九州大学西新プラザ（福岡県福岡市）
  • Year and Date: 2015-10-15
• [Presentation] 石垣島における水平加速度の超伝導重力計への影響 (2015)
  • Author(s): 今西祐一，名和一成，田村良明，池田博，宮地竹史
  • Organizer: 日本地球惑星科学連合2015年大会
  • Place of Presentation: 幕張メッセ国際会議場（千葉県千葉市）
  • Year and Date: 2015-05-28