*Shogo Isayama1, Shuichi Matsukiyo1, Takayoshi Sano2
(1.Interdisciplinary Graduate School of Engineering Sciences, Kyushu University, 2.Institute of Laser Engineering, Osaka University)
Keywords:particle acceleration, counter-propagating Alfvén waves, parametric instability
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).