[P-EM13] 内部磁気圏

[PEM13-14] Plasmaspheric EMIC waves excited through mode conversion from equatorial noise under existence of M/Q=2 ions

*三好 由純¹、松田 昇也²、栗田 怜¹、野村 浩司¹、桂華 邦裕³、小路 真史¹、北村 成寿³、笠原 禎也⁴、松岡 彩子²、篠原 育²、塩川 和夫¹、町田 忍¹、Santolik Ondrej⁵、Boardsen Scott⁶、Horne Richard⁷、John Wygant ⁸ (1.名古屋大学宇宙地球環境研究所、2.宇宙航空研究開発機構、3.東京大学、4.金沢大学、5.チェコ科学アカデミー、6.NASA、7.British Antarctic Survey、8.ミネソタ大学)

キーワード：あらせ、プラズマ圏EMIC、M/Q=2イオン

Equatorial noise (EN, and referred to as magnetosonic mode waves) emissions are observed inside and outside the plasmapause and propagate across the magnetic field. In this study, we found the mode conversion from EN to EMIC waves in the plasmasphere using the plasma wave data from Van Allen Probes and Arase. When EN propagates into the earthward across the field line toward the Earth, EN splits into different waves modes; EN, and EMIC waves with the existence of M/Q=2 ions (deuteron or alpha particles) in the deep plasmasphere and the topside ionosphere. The oblique EMIC waves are excited through this mode conversion process, which are different characteristics of the propagation directions from EMIC waves generated from other processes. This mode conversion contributes to an origin of the plasmaspheric EMIC waves, especially at L<2.