Development of the new technique for ionospheric high frequency radars enabling measurement with a sub-second time resolution of Pc 1-band hydromagnetic waves in the Earth's ionosphere

2017 Fiscal Year Final Research Report

• Project/Area Number: 15K13573
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Space and upper atmospheric physics
• Research Institution: Nagoya University (2015, 2017); The University of Tokyo (2016)
• Principal Investigator: Hori Tomoaki 名古屋大学, 宇宙地球環境研究所, 特任准教授 (30467344)
• Co-Investigator(Renkei-kenkyūsha): NISHITANI Nozomu 名古屋大学, 宇宙地球環境研究所, 准教授 (10218159)
• Project Period (FY): 2015-04-01 – 2018-03-31
• Keywords: 電離圏短波レーダー / Pc 1地磁気脈動 / 高時間分解能観測技術

Outline of Final Research Achievements

This study aimed at development of a new measurement and raw data processing technique for SuperDARN (the network of the ionospheric radars using high frequency radio waves) to deduce the horizontal velocity of ionospheric plasma with a time resolution of the sub-second order. Utilizing the new technique, we tried to measure perturbation in ionospheric plasma velocity caused by the hydromagnetic waves coming from the near-Earth space to the ionosphere and further propagating horizontally in the ionosphere, leading to better understanding of those waves based on an actual observation. As a result, we have successfully developed a technique to observe time variations of the ionospheric plasma velocity with a time resolution of ~0.5s, and possibly with that of ~0.1s, under some good observation conditions. In spite of the efforts to capture the incoming hydromagnetic waves, however, we did not succeed in observing an actual sample of the expected waves so far.

Free Research Field

磁気圏物理学、電離圏物理学、太陽地球系物理学