Large-scale anisotropies of ultra-high-energy cosmic rays measured at the Pierre Auger Observatory

Marta Bianciotto

doi:10.1051/epjconf/202531907001

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arXiv · 2507.19243

Large-scale anisotropies of ultra-high-energy cosmic rays measured at the Pierre Auger Observatory

Marta Bianciotto

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Abstract

Measurements of anisotropies in the arrival directions of ultra-high-energy cosmic rays are crucial to pinpoint their sources, which are yet to be discovered. A dipolar anisotropy in right ascension above 8~EeV has been detected by the Pierre Auger Observatory with a significance of $6.8 \sigma$. The direction of the dipole suggests an extragalactic origin of ultra-high-energy cosmic rays above those energies. In this contribution, we provide an overview of the studies on large-scale anisotropies in the arrival directions of ultra-high-energy cosmic rays measured at the Pierre Auger Observatory with energy thresholds from $\sim 0.03$~EeV up to $32$~EeV and we present and discuss the recent results achieved with the latest available dataset, which includes 19 years of operations -- resulting in a total exposure of 123,000~km$^2$~sr~yr and nearly 50,000 events above 8~EeV.

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Marta Bianciotto. 2025-07-25. Large-scale anisotropies of ultra-high-energy cosmic rays measured at the Pierre Auger Observatory. https://doi.org/10.1051/epjconf%2F202531907001

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