[P-EM08] Inner magnetosphere: Latest results and new perspectives

[PEM08-05] Relation between the ionospheric convection observed by the SuperDARN Hokkaido Paif of (HOP) radars and low-latitude auroras

*西谷 望¹、堀 智昭¹、片岡 龍峰²、海老原 祐輔³、塩川 和夫¹、大塚 雄一¹、鈴木 秀彦⁴ (1.名古屋大学宇宙地球環境研究所、2.国立極地研究所、3.京都大学生存圏研究所、4.明治大学)

キーワード：SuperDARN Hokkaido Pair of (HOP) radars, low-latitude auroras, mid-latitude / subauroral latitude ionospheric convection

Recent SuperDARN deployment toward lower latitudes made it possible to study ionospheric convection associated with low-latitude auroras (up to below 50 degrees geomagnetic latitude) with high temporal resolution (1 min). In this paper we report on the relationship between the appearance of low-latitude auroras for a few geomagnetic storm events (such as that on March 17, 2015 and on December 21, 2015) and ionospheric convection observed by the SuperDARN Hokkaido Pair of (HOP) radars. Associated with low-latitude auroral emission in the postmidnight sector, there was a sheared flow structure with westward flow equatorward of eastward flow, with the equatorward boundary of auroral emission embedded in the westward flow region. Such kind of flow distribution was also observed with other events such as that on January 20, 2016. The observations suggest that the presence of electric field distribution plays some roles in keeping low latitude auroral emission. Detailed discussion of the relationship between the low latitude auroras and the electric field distribution will be presented.