Full-Sky Analysis of Cosmic-Ray Anisotropy with IceCube and HAWC

The HAWC Collaboration; The IceCube Collaboration

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arXiv · 1510.04134

Full-Sky Analysis of Cosmic-Ray Anisotropy with IceCube and HAWC

The HAWC Collaboration·The IceCube Collaboration

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Abstract

During the past two decades, experiments in both the Northern and Southern hemispheres have observed a small but measurable energy-dependent sidereal anisotropy in the arrival direction distribution of galactic cosmic rays. The relative amplitude of the anisotropy is $10^{-4} - 10^{-3}$. However, each of these individual measurements is restricted by limited sky coverage, and so the pseudo-power spectrum of the anisotropy obtained from any one measurement displays a systematic correlation between different multipole modes $C_\ell$. To address this issue, we present the preliminary status of a joint analysis of the anisotropy on all angular scales using cosmic-ray data from the IceCube Neutrino Observatory located at the South Pole ($90^\circ$ S) and the High-Altitude Water Cherenkov (HAWC) Observatory located at Sierra Negra, Mexico ($19^\circ$ N). We describe the methods used to combine the IceCube and HAWC data, address the individual detector systematics and study the region of overlapping field of view between the two observatories.

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The HAWC Collaboration, The IceCube Collaboration. 2015-10-15. Full-Sky Analysis of Cosmic-Ray Anisotropy with IceCube and HAWC. https://arxiv.org/abs/1510.04134

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