[P-EM14] [EE] Dynamics in magnetosphere and ionosphere

[PEM14-27] 東西バンド極方向伝搬型長周期 (T～2-10 min) オーロラ脈動

*佐藤 夏雄^1,2、行松 彰^1,2、田中 良昌^1,2、堀 智昭^3,4、門倉 昭^1,2 (1.国立極地研究所、2.総研大、3.名古屋大学、4.東京大学)

キーワード：オーロラ、東西バンドオーロラ、オーロラ脈動、脈動オーロラ、磁気圏ー電離圏結合、極域現象

Using the ground-based all-sky imagers we examined the long period (T~ 2-10 min) east-west band type auroral pulsations which are completely different from well-known pulsating auroras with period of ~ 10 second. Fundamental characteristics of this type of auroral pulsations are as follows: 1) East-west band auroras extending more than 3000km in some cases, 2) Recurrently poleward moving auroral forms, 3) Recurrent periods are ~ 2-10 min, 4) Auroral intensity enhancement, not intensity modulation, 5) Occurrence region is just poleward side of common pulsating aurora, 6) Occurrence local time is post-midnight sector, 7) Aurora luminosity is rather high, sometimes comparable to discrete auroral arcs in the evening sector. We will examine the generation characteristics and mechanisms of this type of auroral pulsations using the multi-instrument ground-based observations and also the date simultaneously observed with instruments onboard spacecraft.