Study on the electromagnetic environment formed by non-magnetized body in the solar wind

2015 Fiscal Year Final Research Report

• Project/Area Number: 24540480
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Space and upper atmospheric physics
• Research Institution: Tohoku Institute of Technology
• Principal Investigator: Nakagawa Tomoko 東北工業大学, 工学部, 教授 (40222161)
• Co-Investigator(Renkei-kenkyūsha): TSUNAKAWA Hideo 東京工業大学, 大学院理工学研究科, 教授 (40163852) ; SAITO Yoshifumi 宇宙航空研究開発機構, 宇宙科学研究所, 准教授 (30260011)
• Project Period (FY): 2012-04-01 – 2016-03-31
• Keywords: 太陽風 / 月 / 非磁化天体 / ウェイク / プラズマ / 磁場変動 / ＵＬＦ波 / ＥＬＦ波

Outline of Final Research Achievements

The ion entry into the wake behind an obstacle in the solar wind was studied using two-dimensional, electromagnetic full-particle simulations. The Electric field produced by the negative electric charge on the nightside surface of the obstacle accelerates ions toward the void, over longer Debye length than in the solar wind due to the reduced electron density. The ions can access the deepest wake behind a large-scale obstacle being accelerated over a long distance.
Kaguya detected low-frequency magnetic field fluctuations generated by the modified velocity distribution of the solar wind particles reflected or absorbed by the moon. The reflected protons are responsible for the generation of ULF and monochromatic ELF waves through interaction with magnetohydrodynamic and whistler waves in the solar wind. Beams of electrons reflected above the dayside lunar magnetic anomaly, or sucked into the proton rich region in the central wake are the source of broadband ELF waves.

Free Research Field

宇宙空間プラズマ物理学