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arXiv · 1702.01001

Cosmic-Ray Anisotropy and the Local Interstellar Turbulence

Gwenael Giacinti·John G. Kirk
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Abstract

We study the role of local interstellar turbulence in shaping the large-scale anisotropy in the arrival directions of TeV-PeV cosmic-rays (CRs) on the sky. Assuming pitch-angle diffusion of CRs in a magnetic flux tube containing the Earth, we compute the CR anisotropy for Goldreich-Sridhar turbulence, and for isotropic fast modes. The narrow deficits in the 400 TeV and 2 PeV data sets of IceTop can be fitted for some parameters of the turbulence. The data also rule out a part of the parameter space. The shape of the CR anisotropy may be used as a local probe of the still poorly known properties of the interstellar turbulence and of CR transport.

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Gwenael Giacinti, John G. Kirk. 2017-02-03. Cosmic-Ray Anisotropy and the Local Interstellar Turbulence. https://doi.org/10.5281/zenodo.1300184

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