日本地球惑星科学連合2015年大会

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インターナショナルセッション(ポスター発表)

セッション記号 P (宇宙惑星科学) » P-PS 惑星科学

[P-PS04] International Collaboration in Planetary and Space Sciences: Small Projects, Big Missions, Everything

2015年5月27日(水) 18:15 〜 19:30 コンベンションホール (2F)

コンビーナ:*佐々木 晶(大阪大学大学院理学研究科宇宙地球科学専攻)、吉川 顕正(九州大学大学院理学研究院地球惑星科学部門)、Steven Vance(Jet Propulsion Laboratory, Caltech)、Kunio Sayanagi(ハンプトン大学)、関根 康人(東京大学大学院新領域創成科学研究科複雑理工学専攻)、橘 省吾(北海道大学大学院理学研究院自然史科学専攻地球惑星システム科学分野)

18:15 〜 19:30

[PPS04-P04] Science objectives and implementation of Software-type Wave-Particle Interaction Analyzer (SWPIA) by RPWI for JUICE

*加藤 雄人1小嶋 浩嗣2浅村 和史3笠羽 康正1土屋 史紀1笠原 禎也4井町 智彦4三澤 浩昭1熊本 篤志1八木谷 聡4石坂 圭吾5木村 智樹3三好 由純6RPWI-JAPAN, Team 1 (1.東北大学大学院理学研究科、2.京都大学生存圏研究所、3.宇宙航空研究開発機構宇宙科学研究所、4.金沢大学、5.富山県立大学、6.名古屋大学太陽地球環境研究所)

We present science objectives of Software-type Wave-Particle Interaction Analyzer (SWPIA), which will be realized as a software function of Langmuir probes (LP) running on the DPU of RPWI (Radio and Plasma Waves Investigation; PI: J.-E. Wahlund, IRF-Uppsala, Sweden) for the ESA JUICE mission. SWPIA conducts onboard computations of physical quantities indicating the energy exchange between plasma waves and energetic ions. SWPIA cannot be achieved without onboard inter-instruments communications, which will be realized by efforts of RPWI, PEP (Particle Environment Package; PI: Stas Barabash, IR-Kiruna, Sweden) and J-MAG (JUICE Magnetometer; PI: M. Dougherty, ICL, UK). By providing the direct evidence of ion energization processes by plasma waves around Jovian satellites, SWPIA contributes scientific output of JUICE as much as possible with keeping its impact on the telemetry data size to a minimum.
SWPIA measures the energy transfer process between energetic particles and electromagnetic plasma waves [Fukuhara et al., EPS 2009; Katoh et al., AnGeo 2013]. SWPIA will be firstly realized in the ERG satellite mission in the Earth's inner magnetosphere to measure interactions between energetic electrons and whistler-mode chorus. We will apply SWPIA to ion-scale wave-particle interactions occurring in the Jovian magnetosphere. SWPIA clarifies where/when/how heavy ions are energized by waves in the region close to Ganymede and other Jovian satellites. In SWPIA of RPWI for JUICE, we focus on the interactions between energetic ions (a few to tens of keV) and ion cyclotron waves (typically less than 1 Hz). SWPIA uses wave electromagnetic field and ion velocity vectors provided by RPWI sensors and PEP, respectively, with referring three-components of the background magnetic field detected by J-MAG. SWPIA measures a relative phase angle between the velocity vector v_ of i-th particle of charge q_ and the wave electric field vector at the timing of particle's detection (E(t_)) and computes an inner product of W(t_) = q_E(t_) ● v_, where W(t_) corresponds to the variation of the kinetic energy of the i-th energetic particle. We accumulate W for detected particles to obtain Wint = ∑_ W(t_), and we expect statistically significant values of Wint for the case of the measurement at the site of efficient wave-particle interactions. In this presentation, we discuss details of the implementation of SWPIA of RPWI and inter-instruments communications among RPWI-PEP-J-MAG of JUICE.