Trapping of cosmic rays in MHD turbulence
arXiv:2003.12593 · doi:10.3847/1538-4357/ab8465
Abstract
Astrophysical plasmas are turbulent and magnetized. The interaction between cosmic rays (CRs) and magnetohydrodynamic (MHD) turbulence is a fundamental astrophysical process. Based on the current understanding of MHD turbulence, we revisit the trapping of CRs by magnetic mirrors in the context of MHD turbulence. In compressible MHD turbulence, isotropic fast modes dominate both trapping and gyroresonant scattering of CRs. The presence of trapping significantly suppresses the pitch-angle scattering and the spatial diffusion of CRs along the magnetic field. The resulting parallel diffusion coefficient has a weaker dependence on CR energy at higher energies. In incompressible MHD turbulence, the trapping by pseudo-Alfvén modes dominates over the gyroresonant scattering by anisotropic Alfvén and pseudo-Alfvén modes at all pitch angles and prevents CRs from diffusion.
8 pages, 8 figures, accepted for publication in ApJ
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Cited by in corpus (13)
- Diffusion of cosmic rays in MHD turbulence with magnetic mirrors
- Cosmic ray transport in large-amplitude turbulence with small-scale field reversals
- Cosmic ray streaming in the turbulent interstellar medium
- Shock acceleration with oblique and turbulent magnetic fields
- Turbulence and Particle Acceleration in Radiative Shock Waves in the Cygnus Loop II: Development of Postshock Turbulence
- Mirror diffusion of cosmic rays in highly compressible turbulence near supernova remnants
- Cosmic rays and random magnetic traps
- Cosmic ray diffusion in magnetic fields amplified by nonlinear turbulent dynamo
- On the injection scale of the turbulence in the partially ionized very local interstellar medium
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- Chaotic Behavior of Trapped Cosmic Rays
- Diffusion of cosmic rays in MHD turbulence
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