日本地球惑星科学連合2018年大会

講演情報

[JJ] Eveningポスター発表

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-EM17] 宇宙プラズマ理論・シミュレーション

2018年5月23日(水) 17:15 〜 18:30 ポスター会場 (幕張メッセ国際展示場 7ホール)

コンビーナ:梅田 隆行(名古屋大学 宇宙地球環境研究所)、三宅 洋平(神戸大学計算科学教育センター)、成行 泰裕(富山大学人間発達科学部、共同)、中村 匡(福井県立大学)

[PEM17-P04] Non-MHD effects in the nonlinear development of the MHD-scale Rayleigh-Taylor instability

*梅田 隆行1和田 泰尚1 (1.名古屋大学 宇宙地球環境研究所)

キーワード:運動論シミュレーション、無衝突プラズマ、レイリー・テイラー不安定性

The nonlinear evolution of the Rayleigh-Taylor instability (RTI) at a density shear layer transverse to magnetic field in a collisionless plasma is investigated by means of a fully kinetic Vlasov simulation with two spatial and two velocity dimensions. The primary RTI in the MHD regime develops symmetrically in a coordinate axis parallel to gravity as seen in the previous MHD simulations. The primary RTI in the Hall-MHD regime develops asymmetrically in a coordinate axis parallel to gravity. A compressible flow is formed at the secondary density shear layer by the Hall effect, which generates a strong scalar pressure gradient of ions. A Hall electric field due to the diamagnetic current results in the asymmetric flow at the tip of the finger structure. In the primary RTI with the ion gyro kinetic effect, secondary RTI with a wavelength shorter than the wavelength of the primary RTI is generated at the saturation stage of the primary RTI. A seed perturbation for the secondary RTI is excited by another secondary instability due to the coupling between the electron stress tensor and the Hall electric field. The heat flux term plays an important role in the time development of the total pressure. On the other hand, the contribution of the ion stress tensor is small in both the electric current and the total pressure.