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Ultra-high energy cosmic rays: are they isotropic?

Gustavo Medina-Tanco
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Abstract

From the analysis of AGASA data above $4 \times 10^{19}$ eV, we show that the ultra-high energy cosmic rays flux is neither purely isotropic, nor reflects the expected anisotropy from a pure source distribution that maps large scale structure in the local universe. The arrival distribution seems to be the result of a mixture of fluxes (e.g., dark matter halo plus large scale structure) or the superposition of a direct and a diffuse radiation field components respectively. Another viable option is an arbitrary extragalactic flux reprocessed by a magnetized galactic wind model as recently proposed in the literature.

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Gustavo Medina-Tanco. 2000-09-20. Ultra-high energy cosmic rays: are they isotropic?. https://doi.org/10.1086/319467

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