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arXiv · 1112.6388

Apart Cen A are UHECR mostly heavy radioactive and galactic nuclei?

Abstract

Earliest AUGER UHECR anisotropy correlated with AGN within a GZK Universe almost fade away. Recent UHECR mass compositions did show a negligible nucleon composition and an UHECR nuclei (light or heavy) signature. The absence of UHECR events toward the Virgo cluster, an unique spread clustering of events around Cen-A, our nearest AGN, suggested a He-like nuclei as the main extragalactic UHECR component from Cen A, coexisting with Auger and HIRES composition. Because the light nuclei fragility such He UHECR cannot arrive from Virgo. Multiplet at twenty EeV along Cen A recently discovered by Auger confirm this interpretation to be indebt to fragments (D;He3; p) that had to reach us along the same UHECR. Remaining majority of UHECR clustering are partially correlated with a gamma noise at (1-3 MeV) in Comptel sky, linked to Al 26 galactic radioactive map as well as to a few TeV gamma anisotropy maps; rare UHECR triplet are overlapping on Vela TeV anisotropy. Therefore UHECR might be also (or mostly) heavy radioactive galactic nuclei as Ni55, Ni56, Ni57 and Co57 bent from the sources whose gamma and beta radioactivity and decay in flight is boosted (by Lorentz factor near a billion), leading to TeV correlated sky anisotropy. Galactic UHECR signals inside the inner center maybe suppressed by Lorentz bending forces. More clustering around external galactic plane is expected. Magellanic Cloud and Magellanic Stream may also rise in UHECR maps (as well as in multiplet). Future UHECR clustering might be observed around Cas A and Cygnus by T.A. The UHECR spectra cut off may be just the imprint of a galactic confinement and-or a spectroscopic heavy composition decrease step.

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Daniele Fargion. 2012-02-28. Apart Cen A are UHECR mostly heavy radioactive and galactic nuclei?. https://doi.org/10.1088/1742-6596%2F375%2F5%2F052014

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