JpGU-AGU Joint Meeting 2020

講演情報

[E] 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-EM19] Dynamics of the Inner Magnetospheric System

コンビーナ:桂華 邦裕(東京大学大学院理学系研究科地球惑星科学専攻)、Aleksandr Y Ukhorskiy(Johns Hopkins University Applied Physics Laboratory)、三好 由純(名古屋大学宇宙地球環境研究所)、Lynn M Kistler(University of New Hampshire Main Campus)

[PEM19-17] Statistical error estimation of the WPIA method and its application for nonlinear EMIC-proton interactions

*小路 真史1三好 由純1浅村 和史2宮崎 惇史1笠羽 康正3笠原 禎也4松田 昇也2松岡 彩子2Kistler Lynn5,1 (1.名古屋大学宇宙地球環境研究所、2.宇宙科学研究所、3.東北大学、4.金沢大学、5.ニューハンプシャー大学)

キーワード:波動粒子相関解析、EMIC波動、あらせ衛星観測

Theoretical and simulation studies suggest that the EMIC waves with various frequency changes are generated through the nonlinear wave particle interaction with the energetic protons. The nonlinear EMIC emissions with are studied by the Arase satellite data analysis in the Earth’s inner magnetosphere. Wave-particle interaction analysis (WPIA) method which calculate the inner product between the electromagnetic fields and the particle velocities and their phase differences has been developed to show the direct evidence of the energy transfer between the plasma waves and particles. We apply the WPIA method for the EMIC rising tone emissions observed by Arase satellite on 11th Dec. 2017. We perform parametric analyses on the energy and pitch angle of the particles to identify the region causing the efficient energy transfer with the EMIC waves in the proton distribution function. We also show statistical errors which come from the ion particle detector (LEP-i). The errors from the counting statistics and the ambiguity of the looking direction of the ion detectors are estimated. We estimate the minimum integral time in the WPIA method with which we can neglect the counting statistics. The bootstrap method, one of the Monte-Carlo method, is employed to estimate the random sampling errors in the looking direction considering the azimuthal and elevation angle response obtained in laboratory experiments. We discuss significance of the energy transfer by calculating the confidence interval of the WPIA results.