Cosmic-ray pitch-angle scattering in imbalanced mhd turbulence simulations

M.S. Weidl, F. Jenko, B. Teaca, R. Schlickeiser

Research output: Contribution to journalArticle

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Abstract

Pitch-angle scattering rates for cosmic-ray particles in MHD simulations with imbalanced turbulence are calculated for fully evolving electromagnetic turbulence. We compare with theoretical predictions derived from the quasilinear theory of cosmic-ray diffusion for an idealized slab spectrum and demonstrate how cross helicity affects the shape of the pitch-angle diffusion coefficient. Additional simulations in evolving magnetic fields or static field configurations provide evidence that the scattering anisotropy in imbalanced turbulence is not primarily due to coherence with propagating Alfvén waves, but an effect of the spatial structure of electric fields in cross-helical MHD turbulence.
Original languageEnglish
Article number8
JournalAstrophysical Journal
Volume811
Issue number1
DOIs
Publication statusPublished - 11 Sep 2015

Fingerprint

pitch (inclination)
cosmic ray
cosmic rays
turbulence
scattering
simulation
electric field
slab
slabs
anisotropy
diffusion coefficient
electromagnetism
magnetic field
electric fields
prediction
configurations
predictions
magnetic fields

Keywords

  • cosmic rays
  • diffusion
  • magnetohydrodynamics (MHD)
  • scattering

Cite this

Cosmic-ray pitch-angle scattering in imbalanced mhd turbulence simulations. / Weidl, M.S.; Jenko, F.; Teaca, B.; Schlickeiser, R.

In: Astrophysical Journal, Vol. 811, No. 1, 8, 11.09.2015.

Research output: Contribution to journalArticle

Weidl, M.S. ; Jenko, F. ; Teaca, B. ; Schlickeiser, R. / Cosmic-ray pitch-angle scattering in imbalanced mhd turbulence simulations. In: Astrophysical Journal. 2015 ; Vol. 811, No. 1.
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