Cosmic Ray Anisotropy with 11 Years of IceCube Data

Frank McNally; Rasha Abbasi; Paolo Desiati; Juan Carlos Díaz Vélez; Christina Cochling; Katherine Gruchot; William Hayes; Andrew Moy; Emily Schmidt; Andrew Thorpe

arXiv · 2308.02331

Cosmic Ray Anisotropy with 11 Years of IceCube Data

Frank McNally·Rasha Abbasi·Paolo Desiati·Juan Carlos Díaz Vélez·Christina Cochling·Katherine Gruchot·William Hayes·Andrew Moy·Emily Schmidt·Andrew Thorpe

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Abstract

The IceCube Observatory provides our highest-statistics picture of the cosmic-ray arrival directions in the Southern Hemisphere, with over 700 billion cosmic-ray-induced muon events collected between May 2011 and May 2022. Using the larger data volume, we find an improved significance of the PeV cosmic ray anisotropy down to scales of $6^\circ$. In addition, we observe a variation in the angular power spectrum as a function of energy, hinting at a relative decrease in large-scale features above 100 TeV. The data-taking period covers a complete solar cycle, providing new insight into the time variability of the signal. We present preliminary results using this up-to-date event sample.

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Frank McNally, Rasha Abbasi, Paolo Desiati, Juan Carlos Díaz Vélez, Christina Cochling, Katherine Gruchot, William Hayes, Andrew Moy, Emily Schmidt, Andrew Thorpe. 2023-08-04. Cosmic Ray Anisotropy with 11 Years of IceCube Data. https://arxiv.org/abs/2308.02331

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