Modeling of TeV Galactic Cosmic-ray Anisotropy based on Intensity Mapping in an MHD Model Heliosphere

Abstract

Cosmic rays do not arrive at the Earth uniformly. Recent experiments have consistently observed small anisotropies with amplitudes of ∼0.2% in the arrival directions of cosmic rays at TeV energies. We perform the modeling of the cosmic-ray anisotropy at TeV energies using the intensity-mapping method based on Liouville’s theorem. This work indicates unrealistically small-scale ansiotropies with <∼10° angular scales in the distribution of the cosmic-ray relative intensity at the outer boundary of the heliosphere. We would possibly need to resolve an issue that the experimental data covers ten years while the Magnetohydrodynamics (MHD) model heliosphere used in this work is only a single snapshot at a certain moment. Performing the intensity-mapping for multiple snapshots of the MHD model heliosphere and taking the average of the results would improve the results of this work.