[P-EM16] 太陽圏・惑星間空間

[PEM16-P06] On stochastic processes generating non-Gaussian particle distributions in the heliospheric plasma

*成行 泰裕¹、小菅 佑輔²、諌山 翔伍³、羽田 亨⁴ (1.富山大学学術研究部教育学系、2.九州大学応用力学研究所、3.九州大学総合理工学研究院、4.九州大学国際宇宙惑星環境研究センター)

キーワード：太陽圏プラズマ、確率モデル、非ガウス分布

Particle distributions in the heliospheric plasma usually have non-Gaussian characteristics[1]. Whereas the origin of each non-Gaussian distribution is diverse, stochastic modeling of particles is expected to be common in part. Since the stochastic process generating non-Gaussian particle distributions may not be unique, an adequate model should be selected. In this presentation, we revisit stochastic processes generating non-Gaussian particle distributions such as the kappa distribution[2]. By comparing the stochastic differential equations corresponding to Fokker-Planck equations in both Ito and Storatonovich sense[3], physical validity of models is discussed. We will also mention about stochastic models for non-Gaussian distribution observed in different systems such as laboratory plasmas.

[1]e.g., D. Verscharen, K. G. Klein, and B. A. Maruca, Living Rev. Sol. Phys. 16, 5 (2019). [2]e.g., G. Livadiotis and D. J. McComas, J. Geophys. Res., 114, A11105 (2009). [3]e.g., C. Gardiner, Stochastic methods, A handbook for the natural and social sciences. 4th ed. (Springer-Verlag Berlin Heidelberg, 2009).