[P-EM17] 宇宙プラズマ科学

[PEM17-11] Relativistic particle acceleration in two-dimensional Alfvén turblance

*諌山 翔伍¹、松清 修一¹、佐野 孝好² (1.九州大学総合理工学研究院、2.大阪大学レーザー科学研究所)

キーワード：粒子加速、対向伝搬アルフベン波、パラメトリック不安定性

Coherent large amplitude magnetohydrodynamic (MHD) waves are ubiquitous in space and they are considered to play crucial roles in the acceleration of high energy cosmic rays. Various models for generating large amplitude Alfvén waves, associated with cosmic ray acceleration, have been suggested. Previous 1D particle-in-cell simulations demonstrated that counter-propagating Alfvén waves are produced during parametric decay instability in a relativistic pair plasma, leading to efficient particle acceleration [1]. Recent studies have also shown that when the amplitude of these counter-propagating Alfvén waves exceeds a critical value, any particles irreversibly gain relativistic energy within a short time regardless of their initial energy [2]. However, the process of particle acceleration needs further investigation in multi-dimensional spaces to account for the increased channels of parametric instability. In this presentation, we explore particle acceleration within 2D Alfvén wave turbulence.

[1] S. Matsukiyo and T. Hada ApJ. 692, 1004 (2009).
[2] S. Isayama, K. Takahashi, S. Matsukiyo, and T. Sano ApJ. 946, 68 (2023).