Study on the use of optical electric field sensors for the measurement in space

2018 Fiscal Year Final Research Report

• Project/Area Number: 16K13886
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Space and upper atmospheric physics
• Research Institution: Kyoto University
• Principal Investigator: Hirotsugu Kojima 京都大学, 生存圏研究所, 教授 (10215254)
• Research Collaborator: Usui Hideyuki ; Imachi Tomohiko
• Project Period (FY): 2016-04-01 – 2019-03-31
• Keywords: 光電界センサー / 宇宙電磁環境 / プラズマ波動 / 電界観測 / 科学衛星

Outline of Final Research Achievements

Optical electric field sensors are noninvasive sensors. They are commonly used in ground tests. The present research focuses on the use of the optical electric field sensors with top-hat antenna elements on board scientific satellites for observing electric fields of plasma waves in space. The noninvasive feature of the sensor is also the significant advantage for plasma wave measurements in space,. The present research succeeded in showing that the sensitivity of the optical electric field sensors is enough to observe plasma waves with moderate intensities. However, since the sensitivity of the optical electric field sensor is worse than the sensitivity of conventional electric field sensors on board scientific satellites, further improvements should be expected in the use for space science missions. The present research also showed the optical electric field sensors have the immunity for external conductive noise emissions.

Free Research Field

宇宙電波科学

Academic Significance and Societal Importance of the Research Achievements

光電界センサーは非侵襲型のセンサーとして、地上において既に利用されているが、衛星に搭載して宇宙空間で利用することを想定した評価は存在しなかった。本研究により、光電界センサーの宇宙空間での利用に対するポテンシャルを示すことができた意義は大きい。感度的にはまだ不足しているものの、ノイズに対する耐性が非常に強いことは科学観測において非常に重要な特徴であり、将来の衛星観測において、衛星からのノイズや擾乱の影響を受けずに高精度で電界を観測できるシステムが光電界センサーで実現できる可能性が開けた。