JpGU-AGU Joint Meeting 2017

講演情報

[EJ] 口頭発表

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-EM20] [EJ] Heliosphere and Interplanetary Space

2017年5月24日(水) 13:45 〜 15:15 A02 (東京ベイ幕張ホール)

コンビーナ:坪内 健(東京工業大学理学院)、西野 真木(名古屋大学宇宙地球環境研究所)、成行 泰裕(富山大学人間発達科学部)、座長:西野 真木(名古屋大学宇宙地球環境研究所)、座長:塩田 大幸(名古屋大学宇宙地球環境研究所)

15:00 〜 15:15

[PEM20-12] Pickup ion dynamics in the velocity shear layer across the heliopause

*坪内 健1 (1.東京工業大学理学院)

キーワード:pickup ion、heliopause、instability

Consequences of the charge exchange between solar wind plasmas and interstellar neutral particles substantially control the environment of the heliospheric boundary. Recent in-situ observations by Voyager 1/2 and energetic neutral atom (ENA) observations by the Interstellar Boundary Explorer (IBEX) have verified many new features in this region. One of such findings is known as "IBEX ribbon", the bright ENA emissions concentrated in a narrow area. The ribbon geometry is well associated with the local interstellar magnetic field draped on the heliopause, so that the vicinity of the heliopause is its likely source region. The dominant energy range in this ribbon structure (a few keV) indicates that interstellar pickup ions (PUIs) must be the primary source. The purpose of this study is to clarify the physical properties of the ribbon. In this study, we demonstrate hybrid simulations to investigate the dynamics of those PUIs around the heliopause, where the velocity shear might be present between the flow of the solar wind and the interstellar medium. The growth of the Kelvin-Helmholtz instability (KHI) is then expected. We will verify the impact of the presence of PUIs on the KHI properties, the efficiency of the charge exchange, and local concentration of the energetic population and its nonstationarity.