日本地球惑星科学連合2018年大会

講演情報

[EE] Eveningポスター発表

セッション記号 P (宇宙惑星科学) » P-EM 太陽地球系科学・宇宙電磁気学・宇宙環境

[P-EM13] 太陽地球系結合過程の研究基盤形成

2018年5月20日(日) 17:15 〜 18:30 ポスター会場 (幕張メッセ国際展示場 7ホール)

コンビーナ:山本 衛(京都大学生存圏研究所)、小川 泰信(国立極地研究所)、野澤 悟徳(名古屋大学宇宙地球環境研究所、共同)、吉川 顕正(九州大学大学院理学研究院地球惑星科学部門)

[PEM13-P02] 観測ロケットS-520-27号機が観測した中規模伝搬性電離圏擾乱に関連する自然電界とプラズマ密度の解析

*山本 衛1西田 圭吾1石坂 圭吾2田中 真3 (1.京都大学生存圏研究所、2.富山県立大学工学部、3.東海大学情報教育センター)

キーワード:ロケット観測、電界、電子密度分布、中規模電離圏擾乱

Medium-scale traveling ionospheric disturbance (MSTID) is an interesting phenomenon in the F-region. The MSTID is frequent in summer nighttime over Japan, showing wave structures with wavelengths of 100-200 km, periodicity of about 1 hour, and propagation toward the southwest. Although one hypothesis for the generation mechanism of MSTID is suggested by computer simulation, its confirmation by observation is necessary. We had a chance of launching the sounding rockets S-520-27 and S-310-42 to the MSTID region on July 20, 2013 from JAXA Uchinoura Space Center. This study aims to provide accurate data of natural electric field and plasma density from the sounding rocket S-520-27 experiment. Natural electric field was measured by the double-probe sensor on the rocket. The data were analyzed with location and attitude of the rocket and the geomagnetic field model. Accuracy of the analysis is improved as we use the revised rocket attitude that is more accurate than before. Also we propose an estimation method of electric field, which makes use of the orthogonality of the electric field to the geomagnetic field. Obtained natural electric field associated with MSTID was about 5 mV/m. Plasma density from this experiment, on the other hand, was measured by the rocket-ground dual-band beacon experiment. First, total electron content(TEC) was derived from signal processing of the dual-band beacon. Secondly, distribution of plasma density was estimated by tomographic technique. We set the initial data by referring to the data from the impedance probe on the rocket and the three-dimensional GPS-TEC tomography based GEONET. As a result, disordered structure of plasma density with wavelength of 100 km was found. By comparison of these natural electric field and plasma density data, anti-correlation between the two elements was found. In the area of depleted plasma density, the electric field was northeastward, and its intensity became maximum. Above all, this study successfully derived natural electric field and plasma density data which are reasonable for ionosphere behavior and have potentiality for understanding electromagnetic interrelationship between E and F region.