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arXiv · hep-ph/0112014

Ultra High Energy Cosmic Ray and UHE Neutrino-Z Showering in Dark Halos

Abstract

The Ultra High Energy Cosmic Ray (UHECR), by UHE neutrino-relic neutrino--Z showering in Hot Dark Halos (HDM), shows an energy spectra, an anisotropy following the relic neutrino masses and clustering in dark halo. The lighter are the relic neutrinos masses, the higher their corresponding Z resonance energy peaks. A twin light neutrino mass splitting may reflect into a twin Z resonance and a complex UHECR spectra modulation as a twin bump at at highest GZK energy cut-off. Each possible neutrino mass associates a characteristic dark halo size (galactic, local, super cluster) and its anisotropy due to our peculiar position within that dark matter distribution. The expected Z or WW,ZZ showering into proton-anti proton and neutron-anti neutron might correspond to peculiar clustering in observed UHECR at 10^{19}, 2 10^{19}, 4 10^{19} eV. A neutrino light HDM halo around a Mpc will allow to the UHECR neutron--anti-neutron secondary component at E_n> 10^{20} eV (due to Z decay) to arise playing a role comparable with the charged p-bar{p} ones. Their un-deflected n-bar{n} flight is shorter leading to a prompt and hard UHECR trace pointing toward the original UHECR source direction. The direct proton-antiproton pairs are split and spread by random magnetic fields into a more diluted and smeared and lower energy UHECR signal around the original source direction. Additional prompt TeVs signals by synchrotron radiation of electro-magnetic Z showering must also occur solving the Infrared-TeV cut-off. The observed hard doublet and triplets spectra, their time and space clustering already favour the rising key role of UHECR n-bar n secondaries originated by neutrino-Z tail shower.

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BibTeXRIS

Daniele Fargion, P. G. De Sanctis Lucentini, M. Grossi, M. De Santis, Barbara Mele. 2002-01-03. Ultra High Energy Cosmic Ray and UHE Neutrino-Z Showering in Dark Halos. https://arxiv.org/abs/hep-ph/0112014

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