UHECR propagation from Centaurus A

Sarka Wykes; Andrew M. Taylor; Justin D. Bray; Martin J. Hardcastle; Michael Hillas

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arXiv · 1706.08229

UHECR propagation from Centaurus A

Sarka Wykes·Andrew M. Taylor·Justin D. Bray·Martin J. Hardcastle·Michael Hillas

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Abstract

In the light of the recently predicted isotopic composition of the kpc-scale jet in Centaurus A, we re-investigate whether this source could be responsible for some of the ultra-high energy cosmic rays detected by the Pierre Auger Observatory. We find that a nearby source like Centaurus A is well motivated by the composition and spectral shape, and that such sources should start to dominate the flux above ~ 4 EeV. The best-fitting isotopes from our modelling, with the maximum 56Fe energy fixed at 250 EeV, are of intermediate mass, 12C to 16O, while the best-fitting particle index is 2.3.

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Sarka Wykes, Andrew M. Taylor, Justin D. Bray, Martin J. Hardcastle, Michael Hillas. 2017-06-26. UHECR propagation from Centaurus A. https://arxiv.org/abs/1706.08229

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