Ultra high-energy neutrino at GZK energy: Z-WW showering in dark halo   and tau airshowers emerging from the Earth
  Relic neutrino nu_r light masses clustering in Galactic and Local Hot Dark Halos act as a beam dump calorimeter. Ultra High Energy nu, above ZeV, born by AGNs, GRBs at cosmic edges, overcoming (GZK) cut-off, may hit near Z resonance and WW-ZZ channels energies: their showering into UHECR fit observed data . Any tiny neutrino mass splitting may reflect into a twin bump at highest GZK energy cut-off. The Z or WW,ZZ showering explain a peculiar clustering in observed UHECR spectra at 10^19, 210^19, 4 10^19 eV found by AGASA. Coincidence of clustered UHECR with highest gamma BLac sources is well tuned to Z-Showering Scenario. Additional prompt TeVs signals occur offering a natural solution of growing Infrared-TeV cut-off paradoxes related to distant TeV BLac sources and a GRB at TeV energy. Electromagnetic Cascades tail explain correlation found between GeV-EGRET Sources and UHECR. Such UHE nu Astrophysics might trace into Horizontal Tau Air-Showers originated by the UHE nu_tau Earth-Skimming in wide Corona Earth Crust around the observer. These Upward and Horizontal tau Air-Showers UPTAUS, HORTAUS, monitor huge volumes from high mountains as well as observing from planes, balloons and satellites. HORTAUS from mountains observe corona masses at UHE neutrino at EeVs energies comparable to few km^3, while from satellites at orbit altitudes, at GZK energies, their corresponding Horizontal Corona Masses may even exceed 150 km^3. The expected event rate may exceed a dozen of event a year in Z-WW Showering model from satellite. 
D. Fargion