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تسجيل مستخدم جديدUncorrelated far AGN flaring with their delayed UHECRs events
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The most distant AGN, within the allowed GZK cut-off radius, have been recently candidate by many authors as the best location for observed UHECR origination. Indeed, the apparent homogeneity and isotropy of recent UHECR signals seems to require a far cosmic isotropic and homogeneous scenario involving a proton UHECR courier: our galaxy or nearest local group or super galactic plane (ruled by Virgo cluster) are too much near and apparently too much anisotropic in disagreement with PAO and TA almost homogeneous sample data. However, the few and mild observed UHECR clustering, the North and South Hot Spots, are smeared in wide solid angles. Their consequent random walk flight from most far GZK UHECR sources, nearly at 100 Mpc, must be delayed (with respect to a straight AGN photon gamma flaring arrival trajectory) at least by a million years. During this time, the AGN jet blazing signal, its probable axis deflection (such as the helical jet in Mrk501), its miss alignment or even its almost certain exhaust activity may lead to a complete misleading correlation between present UHECR events and a much earlier active AGN ejection. UHECR maps maybe anyway related to galactic or nearest (Cen A, M82) AGN extragalactic UHECR sources shining in twin Hot Spot. Therefore we defend our (quite different) scenarios where UHECR are mostly made by lightest UHECR nuclei originated by nearby AGN sources, or few galactic sources, whose delayed signals reach us within few thousand years in the observed smeared sky areas.
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