日本地球惑星科学連合2016年大会

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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-EM18] 磁気圏-電離圏ダイナミクス

2016年5月25日(水) 13:45 〜 15:15 103 (1F)

コンビーナ:*堀 智昭(名古屋大学宇宙地球環境研究所)、田中 良昌(国立極地研究所)、中溝 葵(情報通信研究機構 電磁波計測研究所)、尾崎 光紀(金沢大学理工研究域電子情報学系)、中野 慎也(情報・システム研究機構 統計数理研究所)、三好 由純(名古屋大学宇宙地球環境研究所)、座長:元場 哲郎(名古屋大学)、尾花 由紀(大阪電気通信大学工学部基礎理工学科)

15:00 〜 15:15

[PEM18-12] 日本経度帯のプラズマ圏密度季節変化:北半球、南半球各々でのMAGDAS磁場観測からの推定・比較

尾上 彩希子2、*河野 英昭1魚住 禎司3Shevtsov Boris4Khomutov Sergey4Poddelskiy Igor4Marshall Richard5吉川 顕正1MAGDAS/CPMN group3 (1.九州大学大学院理学研究院地球惑星科学部門、2.九州大学理学部地球惑星科学科、3.九州大学国際宇宙天気科学・教育センター、4.IKIR FEB RAS, Russia、5.Space Weather Services section, Bureau of Meteorology, Australia)

In this paper we have applied the cross-phase method and the amplitude-ratio method to the MAGDAS/CPMN ground-magnetometer pairs MGD-PTK (Magadan and Paratunka, located in the Russian Far East) and CAN-HOB (Canberra and Hobart, located in eastern Australia), both along the 210MM (Magnetic Meridian), and identified FLR (field-line resonance) events.
MGD is located at (53.6, 219.1) magnetic latitude and longitude [deg], and PTK is located at (46.2, 226.2). Their L values are 2.9 and 2.1. CAN is located at (-45.7, 226.6), and HOB is located at (-54.2, 226.5). Their L values are 2.1 and 2.9. We have identified the FLR events by using both visual inspection and an automatic-identification computer code.
Although the MGD and PTK (CAN and HOB) are separated by about seven (nine) degrees in magnetic latitudes, which is larger than the typical separation (about 1-2 degrees) to which the cross-phase and amplitude-ratio methods are efficient, but we could identify more than a hundred FLR events a year from the both station pairs, and the FLR events had a fairly continuous coverage.
In this paper we estimate the plasmaspheric density from thus obtained FLR frequencies, and examine their seasonal dependence. The result suggests a weak, but marginally significant seasonal dependence with maxima in winter and minima in summer for the both hemispheres. More details will be discussed at the presentation.