Small-Scale Anisotropies of Cosmic Rays from Relative Diffusion
High Energy Astrophysical Phenomena
2015-12-09 v2 High Energy Physics - Phenomenology
Abstract
The arrival directions of multi-TeV cosmic rays show significant anisotropies at small angular scales. It has been argued that this small-scale structure can naturally arise from cosmic ray scattering in local turbulent magnetic fields that distort a global dipole anisotropy set by diffusion. We study this effect in terms of the power spectrum of cosmic ray arrival directions and show that the strength of small-scale anisotropies is related to properties of relative diffusion. We provide a formalism for how these power spectra can be inferred from simulations and motivate a simple analytic extension of the ensemble-averaged diffusion equation that can account for the effect.
Cite
@article{arxiv.1506.05488,
title = {Small-Scale Anisotropies of Cosmic Rays from Relative Diffusion},
author = {Markus Ahlers and Philipp Mertsch},
journal= {arXiv preprint arXiv:1506.05488},
year = {2015}
}
Comments
5 pages, 2 figures, version to appear in ApJL