Implications of turbulence-dependent diffusion on cosmic-ray spectra

J. Dörner; P. Reichherzer; L. Merten; J. Becker Tjus; H. Fichtner; M. J. Pueschel; E. G. Zweibel

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arXiv · 2110.06676

Implications of turbulence-dependent diffusion on cosmic-ray spectra

J. Dörner·P. Reichherzer·L. Merten·J. Becker Tjus·H. Fichtner·M. J. Pueschel·E. G. Zweibel

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Abstract

The propagation of cosmic rays can be described as a diffusive motion in most galactic environments. High-energy gamma-rays measured by Fermi have allowed inference of a gradient in the cosmic-ray density and spectral energy behavior in the Milky Way, which is not predicted by models. Here, a turbulence-dependent diffusion model is used to probe different types of cosmic-ray diffusion tensors. Crucially, it is demonstrated that the observed gradients can be explained through turbulence-dependent energy-scaling of the diffusion tensor.

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J. Dörner, P. Reichherzer, L. Merten, J. Becker Tjus, H. Fichtner, M. J. Pueschel, E. G. Zweibel. 2021-10-13. Implications of turbulence-dependent diffusion on cosmic-ray spectra. https://arxiv.org/abs/2110.06676

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