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arXiv · 2503.13315

Sombrero Galaxy as an Accelerator of Ultrahigh Energy Cosmic Ray Nuclei

Luis A. Anchordoqui·Karem Peñaló Castillo
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Abstract

Motivated by a recent proposal that points to the Sombrero galaxy as a source of the highest energy cosmic rays, we investigate the feasibility of accelerating light and heavy nuclei in the supermassive black hole located at the center of this dormant galaxy. We show that cosmic ray nuclei concentrated in the immediate vicinity of the supermassive black hole could be efficiently accelerated up to the maximum observed energies without suffering catastrophic spallations. Armed with our findings we stand against the conventional wisdom and conjecture that accelerators of the highest energy cosmic rays must anti-correlate with the (electromagnetic) source power.

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Luis A. Anchordoqui, Karem Peñaló Castillo. 2025-03-17. Sombrero Galaxy as an Accelerator of Ultrahigh Energy Cosmic Ray Nuclei. https://arxiv.org/abs/2503.13315

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