Updated Z-Burst Neutrinos at Horizons

Recent homogeneous and isotropic maps of UHECR, suggest an isotropic cosmic origin almost uncorrelated to nearby Local Universe prescribed by GZK (tens Mpc) cut-off. Z-Burst model, based on UHE neutrino resonant scattering on light relic ones in nearby Hot neutrino Dark Halo, may overcome the absence of such a local imprint and explain the recent correlation with BL-Lac at distances of a few hundred Mpc. Z-Burst multiple imprint, due to very possible lightest non-degenerated neutrino masses, may inject energy and modulate UHECR ZeV edge spectra. The Z-burst (and GZK) ultra high energy neutrinos (ZeV and EeV band) may also shine, by UHE neutrinos mass state mixing, and rise in corresponding UHE Tau neutrino flavor, whose charged current tau production and its decay in flight, maybe the source of UHE showering on Earth. The Radius and the atmosphere of our planet constrains the τ maximal distance and energy to make a shower. These terrestrial tau energies are near GZK (1019 eV). Higher distances and energies are available in bigger planets (up to (6⋅1019 eV)); eventual solar atmosphere horizons may amplify the UHE tau flight allowing tau showering at ZeV energies (3.5⋅1020 eV), offering a novel way to reveal the expected Z-Burst extreme neutrino fluxes.